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Solution
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Q.33 Correct
Q.33 In-correct
Q.33 Unattempt
A Spherical ball of radius 1mm and density 10.5gcc is dropped in glycerine of coefficient of viscosity 9.8 poise and density 1.5gcc. Viscous force on the ball when it attains constant velocity is 3696×10xN. The value of x is
(Given, g=9.8m s2 and π=
22
7
)
[24-Jan-2023 Shift 2]
A Spherical ball of radius 1mm and density 10.5gcc is dropped in glycerine of coefficient of viscosity 9.8 poise and density 1.5gcc. Viscous force on the ball when it attains constant velocity is 3696×10xN. The value of x is
(Given, g=9.8m s2 and π=
22
7
)
[24-Jan-2023 Shift 2]
Q.34 Correct
Q.34 In-correct
Q.34 Unattempt
A spherical drop of liquid splits into 1000 identical spherical drops. If ui is the surface energy of the original drop and uf is the total surface energy of the resulting drops, the (ignoring evaporation).
uf
ui
=(
10
x
)
. Then value of x is _______:
[25-Jan-2023 Shift 2]
A spherical drop of liquid splits into 1000 identical spherical drops. If ui is the surface energy of the original drop and uf is the total surface energy of the resulting drops, the (ignoring evaporation).
uf
ui
=(
10
x
)
. Then value of x is _______:
[25-Jan-2023 Shift 2]
Q.35 Correct
Q.35 In-correct
Q.35 Unattempt
Surface tension of a soap bubble is 2.0×102Nm1.
Work done to increase the radius of soap bubble
from 3.5cm to 7cm will be : [Take π=
22
7
]
[29-Jan-2023 Shift 1]
Surface tension of a soap bubble is 2.0×102Nm1.
Work done to increase the radius of soap bubble
from 3.5cm to 7cm will be : [Take π=
22
7
]
[29-Jan-2023 Shift 1]
Q.36 Correct
Q.36 In-correct
Q.36 Unattempt
A fully loaded boeing aircraft has a mass of 5.4×105kg. Its total wing area is 500m2. It is in level flight with a speed of 1080kmh. If the density of air ρ is 1.2kgm3, the fractional increase in the speed of the air on the upper surface of the wing relative to the lower surface in percentage will be (g=10m s2)
[29-Jan-2023 Shift 2]
A fully loaded boeing aircraft has a mass of 5.4×105kg. Its total wing area is 500m2. It is in level flight with a speed of 1080kmh. If the density of air ρ is 1.2kgm3, the fractional increase in the speed of the air on the upper surface of the wing relative to the lower surface in percentage will be (g=10m s2)
[29-Jan-2023 Shift 2]
Q.37 Correct
Q.37 In-correct
Q.37 Unattempt
A metal block of base area 0.20m2 is placed on a table, as shown in figure. A liquid film of thickness 0.25mm is inserted between the block and the table. The block is pushed by a horizontal force of 0.1N and moves with a constant speed. If the viscosity of the liquid is 5.0×103Pl, the speed of block is ______ ×103m s.

[29-Jan-2023 Shift 2]
A metal block of base area 0.20m2 is placed on a table, as shown in figure. A liquid film of thickness 0.25mm is inserted between the block and the table. The block is pushed by a horizontal force of 0.1N and moves with a constant speed. If the viscosity of the liquid is 5.0×103Pl, the speed of block is ______ ×103m s.

[29-Jan-2023 Shift 2]
Q.38 Correct
Q.38 In-correct
Q.38 Unattempt
The height of liquid column raised in a capillary tube of certain radius when dipped in liquid A vertically is, 5cm. If the tube is dipped in a similar manner in another liquid B of surface tension and density double the values of liquid A, the height of liquid column raised in liquid B would be _______ m.
[30-Jan-2023 Shift 1]
The height of liquid column raised in a capillary tube of certain radius when dipped in liquid A vertically is, 5cm. If the tube is dipped in a similar manner in another liquid B of surface tension and density double the values of liquid A, the height of liquid column raised in liquid B would be _______ m.
[30-Jan-2023 Shift 1]
Q.39 Correct
Q.39 In-correct
Q.39 Unattempt
If 1000 droplets of water of surface tension 0.07Nm. having same radius 1mm each, combine to from a single drop. In the process the released surface energy is-
(. Take π=
22
7
)

[31-Jan-2023 Shift 1]
If 1000 droplets of water of surface tension 0.07Nm. having same radius 1mm each, combine to from a single drop. In the process the released surface energy is-
(. Take π=
22
7
)

[31-Jan-2023 Shift 1]
Q.40 Correct
Q.40 In-correct
Q.40 Unattempt
A 100m long wire having cross-sectional area 6.25 ×104m2 and Young's modulus is 1010Nm2 is subjected to a load of 250N, then the elongation in the wire will be :
[24-Jan-2023 Shift 1]
A 100m long wire having cross-sectional area 6.25 ×104m2 and Young's modulus is 1010Nm2 is subjected to a load of 250N, then the elongation in the wire will be :
[24-Jan-2023 Shift 1]
Q.41 Correct
Q.41 In-correct
Q.41 Unattempt
Given below are two statements: one is labelled as
Assertion A and the other is labelled as Reason R
Assertion A: Steel is used in the construction of buildings and bridges.
Reason R: Steel is more elastic and its elastic limit is high.
In the light of above statements, choose the most appropriate answer from the options given below
[24-Jan-2023 Shift 2]
Given below are two statements: one is labelled as
Assertion A and the other is labelled as Reason R
Assertion A: Steel is used in the construction of buildings and bridges.
Reason R: Steel is more elastic and its elastic limit is high.
In the light of above statements, choose the most appropriate answer from the options given below
[24-Jan-2023 Shift 2]
Q.42 Correct
Q.42 In-correct
Q.42 Unattempt
As shown in the figure, in an experiment to determine Young's modulus of a wire, the extension-load curve is plotted. The curve is a straight line passing through the origin and makes an angle of 45 with the load axis. The length of wire is 62.8cm and its diameter is 4 mm. The Young's modulus is found to be x× 104Nm2.
The value of x is _______.

[25-Jan-2023 Shift 1]
As shown in the figure, in an experiment to determine Young's modulus of a wire, the extension-load curve is plotted. The curve is a straight line passing through the origin and makes an angle of 45 with the load axis. The length of wire is 62.8cm and its diameter is 4 mm. The Young's modulus is found to be x× 104Nm2.
The value of x is _______.

 [25-Jan-2023 Shift 1]
Q.43 Correct
Q.43 In-correct
Q.43 Unattempt
An electric bulb is rated as 200W. What will be the peak magnetic field at 4m distance produced by the radiations coming from this bulb? Consider this bulb as a point source with 3.5% efficiency.
[24-Jun-2022-Shift-2]
An electric bulb is rated as 200W. What will be the peak magnetic field at 4m distance produced by the radiations coming from this bulb? Consider this bulb as a point source with 3.5% efficiency.
[24-Jun-2022-Shift-2]
Q.44 Correct
Q.44 In-correct
Q.44 Unattempt
Choose the correct relationship between Poisson ratio (σ). bulk modulus (K) and modulus of rigidity (η) of a given solid object:
[30-Jan-2023 Shift 1]
Choose the correct relationship between Poisson ratio (σ). bulk modulus (K) and modulus of rigidity (η) of a given solid object:
[30-Jan-2023 Shift 1]
Q.45 Correct
Q.45 In-correct
Q.45 Unattempt
A force is applied to a steel wire ' A ', rigidly clamped at one end. As a result elongation in the wire is 0.2mm. If same force is applied to another steel wire ' B ' of double the length and a diameter 2.4 times that of the wire ' A ', the elongation in the wire ' B ' will be (wires having uniform circular cross sections)
[30-Jan-2023 Shift 2]
A force is applied to a steel wire ' A ', rigidly clamped at one end. As a result elongation in the wire is 0.2mm. If same force is applied to another steel wire ' B ' of double the length and a diameter 2.4 times that of the wire ' A ', the elongation in the wire ' B ' will be (wires having uniform circular cross sections)
[30-Jan-2023 Shift 2]
Q.46 Correct
Q.46 In-correct
Q.46 Unattempt
A thin rod having a length of 1m and area of cross-section 3×106m2 is suspended vertically from one end. The rod is cooled from 210C to 160C. After cooling, a mass M is attached at the lower end of the rod such that the length of rod again becomes 1m. Young's modulus and coefficient of linear expansion of the rod are 2×1011Nm2 and 2×105K1, respectively. The value of M is _______ kg. (Take g=10m s2 )
[31-Jan-2023 Shift 1]
A thin rod having a length of 1m and area of cross-section 3×106m2 is suspended vertically from one end. The rod is cooled from 210C to 160C. After cooling, a mass M is attached at the lower end of the rod such that the length of rod again becomes 1m. Young's modulus and coefficient of linear expansion of the rod are 2×1011Nm2 and 2×105K1, respectively. The value of M is _______ kg. (Take g=10m s2 )
[31-Jan-2023 Shift 1]
Q.47 Correct
Q.47 In-correct
Q.47 Unattempt
For a solid rod, the Young's modulus of elasticity is 3.2×1011Nm2 and density is 8×103kgm3. The velocity of longitudinal wave in the rod will be.
[31-Jan-2023 Shift 2]
For a solid rod, the Young's modulus of elasticity is 3.2×1011Nm2 and density is 8×103kgm3. The velocity of longitudinal wave in the rod will be.
[31-Jan-2023 Shift 2]
Q.48 Correct
Q.48 In-correct
Q.48 Unattempt
Under the same load, wire A having length 5.0m and cross section 2.5×105m2 stretches uniformly by the same amount as another wire B of length 6.0m and a cross section of 3.0×105m2 stretches. The ratio of the Young's modulus of wire A to that of wire B will be:
[31-Jan-2023 Shift 2]
Under the same load, wire A having length 5.0m and cross section 2.5×105m2 stretches uniformly by the same amount as another wire B of length 6.0m and a cross section of 3.0×105m2 stretches. The ratio of the Young's modulus of wire A to that of wire B will be:
[31-Jan-2023 Shift 2]
Q.49 Correct
Q.49 In-correct
Q.49 Unattempt
A hole is drilled in a metal sheet. At 27C, the diameter of hole is 5cm. When the sheet is heated to 177C, the change in the diameter of hole is d× 103cm. The value of d will be __________if coefficient of linear expansion of the metal is 1.6× 105C.
[24-Jan-2023 Shift 1]
A hole is drilled in a metal sheet. At 27C, the diameter of hole is 5cm. When the sheet is heated to 177C, the change in the diameter of hole is d× 103cm. The value of d will be __________if coefficient of linear expansion of the metal is 1.6× 105C.
[24-Jan-2023 Shift 1]
Q.50 Correct
Q.50 In-correct
Q.50 Unattempt
A faulty thermometer reads 5C in melting ice and 95C in steam. The correct temperature on absolute scale will be ________ . K when the faulty thermometer reads 41C.
[30-Jan-2023 Shift 2]
A faulty thermometer reads 5C in melting ice and 95C in steam. The correct temperature on absolute scale will be ________ . K when the faulty thermometer reads 41C.
[30-Jan-2023 Shift 2]
Q.51 Correct
Q.51 In-correct
Q.51 Unattempt
A water heater of power 2000W is used to heat water. The specific heat capacity of water is 4200J kg1K1. The efficiency of heater is 70%. Time required to heat 2kg of water from 10C to 60C is _______ s.
(Assume that the specific heat capacity of water remains constant over the temperature range of the water).
[31-Jan-2023 Shift 2]
A water heater of power 2000W is used to heat water. The specific heat capacity of water is 4200J kg1K1. The efficiency of heater is 70%. Time required to heat 2kg of water from 10C to 60C is _______ s.
(Assume that the specific heat capacity of water remains constant over the temperature range of the water).
[31-Jan-2023 Shift 2]
Q.52 Correct
Q.52 In-correct
Q.52 Unattempt
A mercury drop of radius 103m is broken into 125 equal size droplets. Surface tension of mercury is 0.45Nm1. The gain in surface energy is:
[1-Feb-2023 Shift 1]
A mercury drop of radius 103m is broken into 125 equal size droplets. Surface tension of mercury is 0.45Nm1. The gain in surface energy is:
[1-Feb-2023 Shift 1]
Q.53 Correct
Q.53 In-correct
Q.53 Unattempt
The surface of water in a water tank of cross section area 750cm2 on the top of a house is hm. above the tap level. The speed of water coming out through the tap of cross section area 500mm2 is 30cm s. At that instant,
dh
dt
is x×103m s. The value of x will be _______.
[1-Feb-2023 Shift 2]
The surface of water in a water tank of cross section area 750cm2 on the top of a house is hm. above the tap level. The speed of water coming out through the tap of cross section area 500mm2 is 30cm s. At that instant,
dh
dt
is x×103m s. The value of x will be _______.
[1-Feb-2023 Shift 2]
Q.54 Correct
Q.54 In-correct
Q.54 Unattempt
A certain pressure P is applied to 1 litre of water and 2 litre of a liquid separately. Water gets compressed to 0.01% whereas the liquid gets compressed to 0.03%. The ratio of Bulk modulus of water to that of the liquid is
3
x
. The value of x is _______.
[1-Feb-2023 Shift 1]
A certain pressure P is applied to 1 litre of water and 2 litre of a liquid separately. Water gets compressed to 0.01% whereas the liquid gets compressed to 0.03%. The ratio of Bulk modulus of water to that of the liquid is
3
x
. The value of x is _______.
[1-Feb-2023 Shift 1]
Q.55 Correct
Q.55 In-correct
Q.55 Unattempt
The Young's modulus of a steel wire of length 6m and cross-sectional area 3mm2, is 2×1111Nm2. The wire is suspended from its support on a given planet. A block of mass 4kg is attached to the free end of the wire. The acceleration due to gravity on the planet is
1
4
of its value on the earth. The elongation of wire is (Take g on the earth =10 m s2)
[1-Feb-2023 Shift 2]
The Young's modulus of a steel wire of length 6m and cross-sectional area 3mm2, is 2×1111Nm2. The wire is suspended from its support on a given planet. A block of mass 4kg is attached to the free end of the wire. The acceleration due to gravity on the planet is
1
4
of its value on the earth. The elongation of wire is (Take g on the earth =10 m s2)
[1-Feb-2023 Shift 2]
Q.56 Correct
Q.56 In-correct
Q.56 Unattempt
A small ball of mass M and density ρ is dropped in a viscous liquid of density ρ0. After some time, the ball falls with a constant velocity. What is the viscous force on the ball?
[6-Apr-2023 shift 1]
A small ball of mass M and density ρ is dropped in a viscous liquid of density ρ0. After some time, the ball falls with a constant velocity. What is the viscous force on the ball?
[6-Apr-2023 shift 1]
Q.57 Correct
Q.57 In-correct
Q.57 Unattempt
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R
Assertion A : When you squeeze one end of a tube to get toothpaste out from the other end. Pascal's principle is observed.
Reason R : A change in the pressure applied to an enclosed incompressible fluid is transmitted undiminished to every portion of the fluid and to the walls of its container.
In the light of the above statements, choose the most appropriate answer from the options given below
[6-Apr-2023 shift 2]
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R
Assertion A : When you squeeze one end of a tube to get toothpaste out from the other end. Pascal's principle is observed.
Reason R : A change in the pressure applied to an enclosed incompressible fluid is transmitted undiminished to every portion of the fluid and to the walls of its container.
In the light of the above statements, choose the most appropriate answer from the options given below
[6-Apr-2023 shift 2]
Q.58 Correct
Q.58 In-correct
Q.58 Unattempt
An air bubble of volume 1cm3 rises from the bottom of a lake 40m deep to the surface at a temperature of 12C. The atmospheric pressure is 1×105Pa, the density of water is 1000kgm3 and g=10m s2. There is no difference of the temperature of water at the depth of 40m and on the surface. The volume of air bubble when it reaches the surface will be:
[8-Apr-2023 shift 1]
An air bubble of volume 1cm3 rises from the bottom of a lake 40m deep to the surface at a temperature of 12C. The atmospheric pressure is 1×105Pa, the density of water is 1000kgm3 and g=10m s2. There is no difference of the temperature of water at the depth of 40m and on the surface. The volume of air bubble when it reaches the surface will be:
[8-Apr-2023 shift 1]
Q.59 Correct
Q.59 In-correct
Q.59 Unattempt
A hydraulic automobile lift is designed to lift vehicles of mass 5000kg. The area of cross section of the cylinder carrying the load is 250cm2. The maximum pressure the smaller piston would have to bear is [Assume g=10m s2 ] :
[8-Apr-2023 shift 2]
A hydraulic automobile lift is designed to lift vehicles of mass 5000kg. The area of cross section of the cylinder carrying the load is 250cm2. The maximum pressure the smaller piston would have to bear is [Assume g=10m s2 ] :
[8-Apr-2023 shift 2]
Q.60 Correct
Q.60 In-correct
Q.60 Unattempt
Given below are two statements :
Statements I : Pressure in a reservoir of water is same at all points at the same level of water.
Statements II : The pressure applied to enclosed water is transmitted in all directions equally.
In the light of the above statements, choose the correct answer from the options given below :
[10-Apr-2023 shift 1]
Given below are two statements :
Statements I : Pressure in a reservoir of water is same at all points at the same level of water.
Statements II : The pressure applied to enclosed water is transmitted in all directions equally.
In the light of the above statements, choose the correct answer from the options given below :
[10-Apr-2023 shift 1]
Q.61 Correct
Q.61 In-correct
Q.61 Unattempt
Figure below shows a liquid being pushed out of the tube by a piston having area of cross section 2.0cm2. The area of cross section at the outlet is 10mm2. If the piston is pushed at a speed of 4cm s1, the speed of outgoing fluid is _______ cm s1

 [10-Apr-2023 shift 2]
Figure below shows a liquid being pushed out of the tube by a piston having area of cross section 2.0cm2. The area of cross section at the outlet is 10mm2. If the piston is pushed at a speed of 4cm s1, the speed of outgoing fluid is _______ cm s1

 [10-Apr-2023 shift 2]
Q.62 Correct
Q.62 In-correct
Q.62 Unattempt
Eight equal drops of water are falling through air with a steady speed of 10cm s. If the drops collapse, the new velocity is :-
[11-Apr-2023 shift 2]
Eight equal drops of water are falling through air with a steady speed of 10cm s. If the drops collapse, the new velocity is :-
[11-Apr-2023 shift 2]
Q.63 Correct
Q.63 In-correct
Q.63 Unattempt
The surface tension of soap solution is 3.5×102Nm1. The amount of work done required to increase the radius of soap bubble from 10cm to 20cm is ________ ×104J. (take π=227 )
[11-Apr-2023 shift 2]
The surface tension of soap solution is 3.5×102Nm1. The amount of work done required to increase the radius of soap bubble from 10cm to 20cm is ________ ×104J. (take π=227 )
[11-Apr-2023 shift 2]
Q.64 Correct
Q.64 In-correct
Q.64 Unattempt
64 identical drops each charged upto potential of 10mV are combined to form a bigger drop. The potential of the bigger drop will be _______ mV.
[12-Apr-2023 shift 1]
64 identical drops each charged upto potential of 10mV are combined to form a bigger drop. The potential of the bigger drop will be _______ mV.
[12-Apr-2023 shift 1]
Q.65 Correct
Q.65 In-correct
Q.65 Unattempt
Glycerin of density 1.25×103kgm3 is flowing through the conical section of pipe. The area of cross-section of the pipe at its ends are 10cm2 and 5cm2 and pressure drop across its length is 3Nm2. The rate of flow of glycerin through the pipe is x×105m3 s1. The value of x is _______.
[12-Apr-2023 shift 1]
Glycerin of density 1.25×103kgm3 is flowing through the conical section of pipe. The area of cross-section of the pipe at its ends are 10cm2 and 5cm2 and pressure drop across its length is 3Nm2. The rate of flow of glycerin through the pipe is x×105m3 s1. The value of x is _______.
[12-Apr-2023 shift 1]
Q.66 Correct
Q.66 In-correct
Q.66 Unattempt
The figure shows a liquid of given density flowing steadily in horizontal tube of varying cross - section. Cross sectional areas at A is 1.5cm2, and B is 25mm2, if the speed of liquid at B is 60cm s then (PAPB) is: (Given PA and PB are liquid pressures at A and B points)
Density ρ=1000kgm3
A and B are on the axis of tube

[13-Apr-2023 shift 1]
The figure shows a liquid of given density flowing steadily in horizontal tube of varying cross - section. Cross sectional areas at A is 1.5cm2, and B is 25mm2, if the speed of liquid at B is 60cm s then (PAPB) is: (Given PA and PB are liquid pressures at A and B points)
Density ρ=1000kgm3
A and B are on the axis of tube

[13-Apr-2023 shift 1]
Q.67 Correct
Q.67 In-correct
Q.67 Unattempt
Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R
Assertion A : A spherical body of radius (5±0.1)mm having a particular density is falling through a liquid of constant density. The percentage error in the calculation of its terminal velocity is 4%
Reason R : The terminal velocity of the spherical body falling through the liquid is inversely proportional to its radius.
In the light of the above statements, choose the correct answer from the options given below
[13-Apr-2023 shift 2]
Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R
Assertion A : A spherical body of radius (5±0.1)mm having a particular density is falling through a liquid of constant density. The percentage error in the calculation of its terminal velocity is 4%
Reason R : The terminal velocity of the spherical body falling through the liquid is inversely proportional to its radius.
In the light of the above statements, choose the correct answer from the options given below
[13-Apr-2023 shift 2]
Q.68 Correct
Q.68 In-correct
Q.68 Unattempt
There is an air bubble of radius 1.0mm in a liquid of surface tension 0.075nm1 and density 1000kgm3 at a depth of 10cm below the free surface. The amount by which the pressure inside the bubble is greater than the atmospheric pressure is ________ Pa(g=10ms2)
[15-Apr-2023 shift 1]
There is an air bubble of radius 1.0mm in a liquid of surface tension 0.075nm1 and density 1000kgm3 at a depth of 10cm below the free surface. The amount by which the pressure inside the bubble is greater than the atmospheric pressure is ________ Pa(g=10ms2)
[15-Apr-2023 shift 1]
Q.69 Correct
Q.69 In-correct
Q.69 Unattempt
A metal block of mass m is suspended from a rigid support through a metal wire of diameter 14mm. The tensile stress developed in the wire under equilibrium state is 7×105Nm2. The value of mass m is _______ kg.
(Take, g=9.8ms2 and π=
22
7
)
[6-Apr-2023 shift 2]
A metal block of mass m is suspended from a rigid support through a metal wire of diameter 14mm. The tensile stress developed in the wire under equilibrium state is 7×105Nm2. The value of mass m is _______ kg.
(Take, g=9.8ms2 and π=
22
7
)
[6-Apr-2023 shift 2]
Q.70 Correct
Q.70 In-correct
Q.70 Unattempt
An aluminium rod with Young's modulus Y=7.0×1010Nm2 undergoes elastic strain of 0.04%. The energy per unit volume stored in the rod in SI unit is:
[8-Apr-2023 shift 1]
An aluminium rod with Young's modulus Y=7.0×1010Nm2 undergoes elastic strain of 0.04%. The energy per unit volume stored in the rod in SI unit is:
[8-Apr-2023 shift 1]
Q.71 Correct
Q.71 In-correct
Q.71 Unattempt
Two wires each of radius 0.2cm and negligible mass, one made of steel and the other made of brass are loaded as shown in the figure. The elongation of the steel wire is ______ ×106m. [Young's modulus for steel =2× 1011Nm2 and g=10ms2

[10-Apr-2023 shift 1]
Two wires each of radius 0.2cm and negligible mass, one made of steel and the other made of brass are loaded as shown in the figure. The elongation of the steel wire is ______ ×106m. [Young's modulus for steel =2× 1011Nm2 and g=10ms2

[10-Apr-2023 shift 1]
Q.72 Correct
Q.72 In-correct
Q.72 Unattempt
Young's moduli of the material of wires A and B are in the ratio of 1:4, while its area of cross sections are in the ratio of 1:3. If the same amount of load is applied to both the wires, the amount of elongation produced in the wires A and B will be in the ratio of [Assume length of wires A and B are same]
[10-Apr-2023 shift 2]
Young's moduli of the material of wires A and B are in the ratio of 1:4, while its area of cross sections are in the ratio of 1:3. If the same amount of load is applied to both the wires, the amount of elongation produced in the wires A and B will be in the ratio of [Assume length of wires A and B are same]
[10-Apr-2023 shift 2]
Q.73 Correct
Q.73 In-correct
Q.73 Unattempt
The length of a wire becomes l1 and l2 when 100N and 120N tensions are applied respectively. If 10l2=11ll, the natural length of wire will be
1
x
l1
. Here the value of x is ________.
[11-Apr-2023 shift 1]
The length of a wire becomes l1 and l2 when 100N and 120N tensions are applied respectively. If 10l2=11ll, the natural length of wire will be
1
x
l1
. Here the value of x is ________.
[11-Apr-2023 shift 1]
Q.74 Correct
Q.74 In-correct
Q.74 Unattempt
Under isothermal condition, the pressure of a gas is given by P=aV3, where a is a constant and V is the volume of the gas. The bulk modulus at constant temperature is equal to
[13-Apr-2023 shift 1]
Under isothermal condition, the pressure of a gas is given by P=aV3, where a is a constant and V is the volume of the gas. The bulk modulus at constant temperature is equal to
[13-Apr-2023 shift 1]
Q.75 Correct
Q.75 In-correct
Q.75 Unattempt
The elastic potential energy stored in a steel wire of length 20m stretched through 2cm is 80J. The cross sectional area of the wire is ________ (. Given, y=2.0×1011Nm2 ) mm2.
[13-Apr-2023 shift 1]
The elastic potential energy stored in a steel wire of length 20m stretched through 2cm is 80J. The cross sectional area of the wire is ________ (. Given, y=2.0×1011Nm2 ) mm2.
[13-Apr-2023 shift 1]
Q.76 Correct
Q.76 In-correct
Q.76 Unattempt
A wire of length ' L ' and radius ' r ' is clamped rigidly at one end. When the other end of the wire is pulled by a force f, its length increases by ' l '. Another wire of same material of length ' 2L ' and radius ' 2r ' is pulled by a force ' 2f. Then the increase in its length will be :
[15-Apr-2023 shift 1]
A wire of length ' L ' and radius ' r ' is clamped rigidly at one end. When the other end of the wire is pulled by a force f, its length increases by ' l '. Another wire of same material of length ' 2L ' and radius ' 2r ' is pulled by a force ' 2f. Then the increase in its length will be :
[15-Apr-2023 shift 1]
Q.77 Correct
Q.77 In-correct
Q.77 Unattempt
A body cools in 7 minutes from 60C to 40C. The temperature of the surrounding is 10C. The temperature of the body after the next 7 minutes
[6-Apr-2023 shift 2]
A body cools in 7 minutes from 60C to 40C. The temperature of the surrounding is 10C. The temperature of the body after the next 7 minutes
[6-Apr-2023 shift 2]
Q.78 Correct
Q.78 In-correct
Q.78 Unattempt
A steel rod of length 1m and cross sectional area 104m2 is heated from 0C to 200C without being allowed to extend or bend. The compressive tension produced in the rod is ________ of steel =2×1011Nm2, coefficient of linear expansion =105K1 ) ×104N. (Given Young's modulus
[8-Apr-2023 shift 2]
A steel rod of length 1m and cross sectional area 104m2 is heated from 0C to 200C without being allowed to extend or bend. The compressive tension produced in the rod is ________ of steel =2×1011Nm2, coefficient of linear expansion =105K1 ) ×104N. (Given Young's modulus
[8-Apr-2023 shift 2]
Q.79 Correct
Q.79 In-correct
Q.79 Unattempt
1kg of water at 100C is converted into steam at 100C by boiling at atmospheric pressure. The volume of water changes from 1.00×103m3 as a liquid to 1.671m3 as steam. The change in internal energy of the system during the process will be
(Given latent heat of vaporisation =2257kJkg, Atmospheric pressure =1×105Pa )
[11-Apr-2023 shift 1]
1kg of water at 100C is converted into steam at 100C by boiling at atmospheric pressure. The volume of water changes from 1.00×103m3 as a liquid to 1.671m3 as steam. The change in internal energy of the system during the process will be
(Given latent heat of vaporisation =2257kJkg, Atmospheric pressure =1×105Pa )
[11-Apr-2023 shift 1]
Q.80 Correct
Q.80 In-correct
Q.80 Unattempt
On a temperature scale ' X ', the boiling point of water is 65X and the freezing point is 15X. Assume that the X scale is linear. The equivalent temperature corresponding to 95X on the Farenheit scale would be :
[11-Apr-2023 shift 1]
On a temperature scale ' X ', the boiling point of water is 65X and the freezing point is 15X. Assume that the X scale is linear. The equivalent temperature corresponding to 95X on the Farenheit scale would be :
[11-Apr-2023 shift 1]
Q.81 Correct
Q.81 In-correct
Q.81 Unattempt
A body cools from 80C to 60C in 5 minutes. The temperature of the surrounding is 20C. The time it takes to cool from 60C to 40C is:
[12-Apr-2023 shift 1]
A body cools from 80C to 60C in 5 minutes. The temperature of the surrounding is 20C. The time it takes to cool from 60C to 40C is:
[12-Apr-2023 shift 1]
Q.82 Correct
Q.82 In-correct
Q.82 Unattempt
Two plates A and B have thermal conductivities 84Wm1K1 and 126Wm1K1 respectively. They have same surface area and same thickness. They are placed in contact along their surfaces. If the temperatures of the outer surfaces of A and B are kept at 100C and 0C respectively, then the temperature of the surface of contact in steady state is ______ C.
[13-Apr-2023 shift 2]
Two plates A and B have thermal conductivities 84Wm1K1 and 126Wm1K1 respectively. They have same surface area and same thickness. They are placed in contact along their surfaces. If the temperatures of the outer surfaces of A and B are kept at 100C and 0C respectively, then the temperature of the surface of contact in steady state is ______ C.
[13-Apr-2023 shift 2]
Q.83 Correct
Q.83 In-correct
Q.83 Unattempt
The terminal velocity (vt) of the spherical rain drop depends on the radius (r) of the spherical rain drop as :
[25-Jun-2022-Shift-1]
The terminal velocity (vt) of the spherical rain drop depends on the radius (r) of the spherical rain drop as :
[25-Jun-2022-Shift-1]
Q.84 Correct
Q.84 In-correct
Q.84 Unattempt
The velocity of upper layer of water in a river is 36kmh1. Shearing stress between horizontal layers of water is 103Nm2. Depth of the river is m. (Co-efficient of viscosity of water is _____102Pa.s )
[25-Jun-2022-Shift-1]
The velocity of upper layer of water in a river is 36kmh1. Shearing stress between horizontal layers of water is 103Nm2. Depth of the river is m. (Co-efficient of viscosity of water is _____102Pa.s )
[25-Jun-2022-Shift-1]
Q.85 Correct
Q.85 In-correct
Q.85 Unattempt
An ideal fluid of density 800kgm3, flows smoothly through a bent pipe (as shown in figure) that tapers in cross-sectional area from a to
a
2
. The pressure difference between the wide and narrow sections of pipe is 4100Pa. At wider section, the velocity of fluid is
x
6
ms1
for x= (Given g=10ms2 )

[26-Jun-2022-Shift-1]
An ideal fluid of density 800kgm3, flows smoothly through a bent pipe (as shown in figure) that tapers in cross-sectional area from a to
a
2
. The pressure difference between the wide and narrow sections of pipe is 4100Pa. At wider section, the velocity of fluid is
x
6
ms1
for x= (Given g=10ms2 )

[26-Jun-2022-Shift-1]
Q.86 Correct
Q.86 In-correct
Q.86 Unattempt
If p is the density and η is coefficient of viscosity of fluid which flows with a speed v in the pipe of diameter d, the correct formula for Reynolds number Re is :
[26-Jun-2022-Shift-2]
If p is the density and η is coefficient of viscosity of fluid which flows with a speed v in the pipe of diameter d, the correct formula for Reynolds number Re is :
[26-Jun-2022-Shift-2]
Q.87 Correct
Q.87 In-correct
Q.87 Unattempt
The velocity of a small ball of mass ' m ' and density d1, when dropped in a container filled with glycerin, becomes constant after some time. If the density of glycerin is d2, then the viscous force acting on the ball, will be :
[27-Jun-2022-Shift-1]
The velocity of a small ball of mass ' m ' and density d1, when dropped in a container filled with glycerin, becomes constant after some time. If the density of glycerin is d2, then the viscous force acting on the ball, will be :
[27-Jun-2022-Shift-1]
Q.88 Correct
Q.88 In-correct
Q.88 Unattempt
The area of cross-section of a large tank is 0.5m2. It has a narrow opening near the bottom having area of cross-section 1cm. A load of 25kg is applied on the water at the top in the tank. Neglecting the speed of water in the tank, the velocity of the water, coming out of the opening at the time when the height of water level in the tank is 40cm above the bottom, will be ____cms1[. Take g=10ms2 ]
[27-Jun-2022-Shift-1]
The area of cross-section of a large tank is 0.5m2. It has a narrow opening near the bottom having area of cross-section 1cm. A load of 25kg is applied on the water at the top in the tank. Neglecting the speed of water in the tank, the velocity of the water, coming out of the opening at the time when the height of water level in the tank is 40cm above the bottom, will be ____cms1[. Take g=10ms2 ]
[27-Jun-2022-Shift-1]
Q.89 Correct
Q.89 In-correct
Q.89 Unattempt
When a ball is dropped into a lake from a height 4.9m above the water level, it hits the water with a velocity v and then sinks to the bottom with the constant velocity v. It reaches the bottom of the lake 4.0s after it is dropped. The approximate depth of the lake is :
[27-Jun-2022-Shift-2]
When a ball is dropped into a lake from a height 4.9m above the water level, it hits the water with a velocity v and then sinks to the bottom with the constant velocity v. It reaches the bottom of the lake 4.0s after it is dropped. The approximate depth of the lake is :
[27-Jun-2022-Shift-2]
Q.90 Correct
Q.90 In-correct
Q.90 Unattempt
Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : Product of Pressure (P) and time (t) has the same dimension as that of coefficient of viscosity.
Reason R : Coefficient of viscosity =
Force
Velocity gradient

Choose the correct answer from the options given below :
[28-Jun-2022-Shift-1]
Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : Product of Pressure (P) and time (t) has the same dimension as that of coefficient of viscosity.
Reason R : Coefficient of viscosity =
Force
Velocity gradient

Choose the correct answer from the options given below :
[28-Jun-2022-Shift-1]
Q.91 Correct
Q.91 In-correct
Q.91 Unattempt
A water drop of diameter 2cm is broken into 64 equal droplets. The surface tension of water is 0.075Nm. In this process the gain in surface energy will be :
[28-Jun-2022-Shift-1]
A water drop of diameter 2cm is broken into 64 equal droplets. The surface tension of water is 0.075Nm. In this process the gain in surface energy will be :
[28-Jun-2022-Shift-1]
Q.92 Correct
Q.92 In-correct
Q.92 Unattempt
A water drop of radius 1µm falls in a situation where the effect of buoyant force is negligible. Co-efficient of viscosity of air is 1.8×105Nsm2 and its density is negligible as compared to that of water 106gm3. Terminal velocity of the water drop is
(Take acceleration due to gravity =10ms2 )
[28-Jun-2022-Shift-2]
A water drop of radius 1µm falls in a situation where the effect of buoyant force is negligible. Co-efficient of viscosity of air is 1.8×105Nsm2 and its density is negligible as compared to that of water 106gm3. Terminal velocity of the water drop is
(Take acceleration due to gravity =10ms2 )
[28-Jun-2022-Shift-2]
Q.93 Correct
Q.93 In-correct
Q.93 Unattempt
A liquid of density 750kgm3 flows smoothly through a horizontal pipe that tapers in cross-sectional area from A1=1.2×10 2m2 to A2=
A1
2
. The pressure difference between the wide and narrow sections of the pipe is 4500Pa. The rate of flow of liquid is _____×103m3s1
[28-Jun-2022-Shift-2]
A liquid of density 750kgm3 flows smoothly through a horizontal pipe that tapers in cross-sectional area from A1=1.2×10 2m2 to A2=
A1
2
. The pressure difference between the wide and narrow sections of the pipe is 4500Pa. The rate of flow of liquid is _____×103m3s1
[28-Jun-2022-Shift-2]
Q.94 Correct
Q.94 In-correct
Q.94 Unattempt
A small spherical ball of radius 0.1mm and density 104kgm3 falls freely under gravity through a distance h before entering a tank of water. If, after entering the water the velocity of ball does not change and it continue to fall with same constant velocity inside water, then the value of h will be _____m.
(Given g=10ms2, viscosity of water =1.0×105Nsm2 ).
[29-Jun-2022-Shift-2]
A small spherical ball of radius 0.1mm and density 104kgm3 falls freely under gravity through a distance h before entering a tank of water. If, after entering the water the velocity of ball does not change and it continue to fall with same constant velocity inside water, then the value of h will be _____m.
(Given g=10ms2, viscosity of water =1.0×105Nsm2 ).
[29-Jun-2022-Shift-2]
Q.95 Correct
Q.95 In-correct
Q.95 Unattempt
The bulk modulus of a liquid is 3×1010Nm2. The pressure required to reduce the volume of liquid by 2% is :
[24-Jun-2022-Shift-1]
The bulk modulus of a liquid is 3×1010Nm2. The pressure required to reduce the volume of liquid by 2% is :
[24-Jun-2022-Shift-1]
Q.96 Correct
Q.96 In-correct
Q.96 Unattempt
The elastic behaviour of material for linear stress and linear strain, is shown in the figure. The energy density for a linear strain of 5×104 is_____ kJm3. Assume that material is elastic upto the linear strain of 5×104.
[26-Jun-2022-Shift-1]
The elastic behaviour of material for linear stress and linear strain, is shown in the figure. The energy density for a linear strain of 5×104 is_____ kJm3. Assume that material is elastic upto the linear strain of 5×104.
[26-Jun-2022-Shift-1]
Q.97 Correct
Q.97 In-correct
Q.97 Unattempt
Two metallic blocks M1 and M2 of same area of cross-section are connected to each other (as shown in figure). If the thermal conductivity of M2 is K then the thermal conductivity of M1 will be :
[Assume steady state heat conduction]

[24-Jun-2022-Shift-1]
Two metallic blocks M1 and M2 of same area of cross-section are connected to each other (as shown in figure). If the thermal conductivity of M2 is K then the thermal conductivity of M1 will be :
[Assume steady state heat conduction]

[24-Jun-2022-Shift-1]
Q.98 Correct
Q.98 In-correct
Q.98 Unattempt
A 100g of iron nail is hit by a 1.5kg hammer striking at a velocity of 60ms1. What will be the rise in the temperature of the nail if one fourth of energy of the hammer goes into heating the nail?
[Specific heat capacity of iron =0.42Jg1C1 ]
[24-Jun-2022-Shift-2]
A 100g of iron nail is hit by a 1.5kg hammer striking at a velocity of 60ms1. What will be the rise in the temperature of the nail if one fourth of energy of the hammer goes into heating the nail?
[Specific heat capacity of iron =0.42Jg1C1 ]
[24-Jun-2022-Shift-2]
Q.99 Correct
Q.99 In-correct
Q.99 Unattempt
In an experiment to verify Newton's law of cooling, a graph is plotted between the temperature difference (T) of the water and surroundings and time as shown in figure. The initial temperature of water is taken as 80C. The value of t2 as mentioned in the graph will be

[24-Jun-2022-Shift-2]
In an experiment to verify Newton's law of cooling, a graph is plotted between the temperature difference (T) of the water and surroundings and time as shown in figure. The initial temperature of water is taken as 80C. The value of t2 as mentioned in the graph will be

[24-Jun-2022-Shift-2]
Q.100 Correct
Q.100 In-correct
Q.100 Unattempt
A steam engine intakes 50g of steam at 100C per minute and cools it down to 20C. If latent heat of vaporization of steam is 540calg1, then the heat rejected by the steam engine per minute is _____× 103cal
(Given : specific heat capacity of water : 1calg1C1 )
[25-Jun-2022-Shift-1]
A steam engine intakes 50g of steam at 100C per minute and cools it down to 20C. If latent heat of vaporization of steam is 540calg1, then the heat rejected by the steam engine per minute is _____× 103cal
(Given : specific heat capacity of water : 1calg1C1 )
[25-Jun-2022-Shift-1]
Q.101 Correct
Q.101 In-correct
Q.101 Unattempt
A solid metallic cube having total surface area 24m2 is uniformly heated. If its temperature is increased by 10C, calculate the increase in volume of the cube. (. Given .α=5.0×104C1)
[25-Jun-2022-Shift-2]
A solid metallic cube having total surface area 24m2 is uniformly heated. If its temperature is increased by 10C, calculate the increase in volume of the cube. (. Given .α=5.0×104C1)
[25-Jun-2022-Shift-2]
Q.102 Correct
Q.102 In-correct
Q.102 Unattempt
A copper block of mass 5.0kg is heated to a temperature of 500C and is placed on a large ice block. What is the maximum amount of ice that can melt? [Specific heat of copper : 0.39Jg1C1 and latent heat of fusion of water : 335Jg1 ]
[25-Jun-2022-Shift-2]
A copper block of mass 5.0kg is heated to a temperature of 500C and is placed on a large ice block. What is the maximum amount of ice that can melt? [Specific heat of copper : 0.39Jg1C1 and latent heat of fusion of water : 335Jg1 ]
[25-Jun-2022-Shift-2]
Q.103 Correct
Q.103 In-correct
Q.103 Unattempt
A geyser heats water flowing at a rate of 2.0kg per minute from 30C to 70C. If geyser operates on a gas burner, the rate of combustion of fuel will be _____ gmin1
[Heat of combustion =8×103Jg1, Specific heat of water =4.2Jg1C1 ]
[26-Jun-2022-Shift-2]
A geyser heats water flowing at a rate of 2.0kg per minute from 30C to 70C. If geyser operates on a gas burner, the rate of combustion of fuel will be _____ gmin1
[Heat of combustion =8×103Jg1, Specific heat of water =4.2Jg1C1 ]
[26-Jun-2022-Shift-2]
Q.104 Correct
Q.104 In-correct
Q.104 Unattempt
A lead bullet penetrates into a solid object and melts. Assuming that 40% of its kinetic energy is used to heat it, the initial speed of bullet is :
(Given : initial temperature of the bullet =127C, Melting point of the bullet =327C, Latent heat of fusion of lead =2.5×104J kg1, Specific heat capacity of lead .=125JkgK)
[27-Jun-2022-Shift-2]
A lead bullet penetrates into a solid object and melts. Assuming that 40% of its kinetic energy is used to heat it, the initial speed of bullet is :
(Given : initial temperature of the bullet =127C, Melting point of the bullet =327C, Latent heat of fusion of lead =2.5×104J kg1, Specific heat capacity of lead .=125JkgK)
[27-Jun-2022-Shift-2]
Q.105 Correct
Q.105 In-correct
Q.105 Unattempt
Resistance of the wire is measured as 2 and 3 at 10C and 30C respectively. Temperature co-efficient of resistance of the material of the wire is :
[28-Jun-2022-Shift-2]
Resistance of the wire is measured as 2 and 3 at 10C and 30C respectively. Temperature co-efficient of resistance of the material of the wire is :
[28-Jun-2022-Shift-2]
Q.106 Correct
Q.106 In-correct
Q.106 Unattempt
As per the given figure, two plates A and B of thermal conductivity K and 2K are joined together to form a compound plate.
The thickness of plates are 4.0cm and 2.5cm respectively and the area of cross-section is 120cm2 for each plate. The equivalent thermal conductivity of the compound plate is (1+
5
α
)
K
, then the value of α will be______

[29-Jun-2022-Shift-1]
As per the given figure, two plates A and B of thermal conductivity K and 2K are joined together to form a compound plate.
The thickness of plates are 4.0cm and 2.5cm respectively and the area of cross-section is 120cm2 for each plate. The equivalent thermal conductivity of the compound plate is (1+
5
α
)
K
, then the value of α will be______

[29-Jun-2022-Shift-1]
Q.107 Correct
Q.107 In-correct
Q.107 Unattempt
At what temperature a gold ring of diameter 6.230cm be heated so that it can be fitted on a wooden bangle of diameter 6.241cm ? Both the diameters have been measured at room temperature (27C).
(Given : coefficient of linear thermal expansion of gold αL=1.4×105K1 )
[29-Jun-2022-Shift-2]
At what temperature a gold ring of diameter 6.230cm be heated so that it can be fitted on a wooden bangle of diameter 6.241cm ? Both the diameters have been measured at room temperature (27C).
(Given : coefficient of linear thermal expansion of gold αL=1.4×105K1 )
[29-Jun-2022-Shift-2]
Q.108 Correct
Q.108 In-correct
Q.108 Unattempt
A drop of liquid of density ρ is floating half immersed in a liquid of density boldsymbolσ and surface tension 7.5×104Ncm1. The radius of drop in cm will be :
(g=10ms2)
[25-Jul-2022-Shift-2]
A drop of liquid of density ρ is floating half immersed in a liquid of density boldsymbolσ and surface tension 7.5×104Ncm1. The radius of drop in cm will be :
(g=10ms2)
[25-Jul-2022-Shift-2]
Q.109 Correct
Q.109 In-correct
Q.109 Unattempt
A water drop of radius 1cm is broken into 729 equal droplets. If surface tension of water is 75 dyne\/ cm, then the gain in surface energy upto first decimal place will be :
(Given π=3.14 )
[26-Jul-2022-Shift-1]
A water drop of radius 1cm is broken into 729 equal droplets. If surface tension of water is 75 dyne\/ cm, then the gain in surface energy upto first decimal place will be :
(Given π=3.14 )
[26-Jul-2022-Shift-1]
Q.110 Correct
Q.110 In-correct
Q.110 Unattempt
Two cylindrical vessels of equal cross-sectional area 16cm2 contain water upto heights 100cm and 150cm respectively. The vessels are interconnected so that the water levels in them become equal. The work done by the force of gravity during the process, is [Take, density of water =103kgm3 and .g=10ms2] :
[27-Jul-2022-Shift-1]
Two cylindrical vessels of equal cross-sectional area 16cm2 contain water upto heights 100cm and 150cm respectively. The vessels are interconnected so that the water levels in them become equal. The work done by the force of gravity during the process, is [Take, density of water =103kgm3 and .g=10ms2] :
[27-Jul-2022-Shift-1]
Q.111 Correct
Q.111 In-correct
Q.111 Unattempt
A spherical soap bubble of radius 3cm is formed inside another spherical soap bubble of radius 6 cm. If the internal pressure of the smaller bubble of radius 3cm in the above system is equal to the internal pressure of the another single soap bubble of radius rcm. The value of r is _________.
[27-Jul-2022-Shift-2]
A spherical soap bubble of radius 3cm is formed inside another spherical soap bubble of radius 6 cm. If the internal pressure of the smaller bubble of radius 3cm in the above system is equal to the internal pressure of the another single soap bubble of radius rcm. The value of r is _________.
[27-Jul-2022-Shift-2]
Q.112 Correct
Q.112 In-correct
Q.112 Unattempt
The diameter of an air bubble which was initially 2mm, rises steadily through a solution of density 1750kgm3 at the rate of 0.35cms1. The coefficient of viscosity of the solution is _______ poise (in nearest integer). (the density of air is negligible).
[28-Jul-2022-Shift-1]
The diameter of an air bubble which was initially 2mm, rises steadily through a solution of density 1750kgm3 at the rate of 0.35cms1. The coefficient of viscosity of the solution is _______ poise (in nearest integer). (the density of air is negligible).
[28-Jul-2022-Shift-1]
Q.113 Correct
Q.113 In-correct
Q.113 Unattempt
A pressure-pump has a horizontal tube of cross sectional area 10cm2 for the outflow of water at a speed of 20m s. The force exerted on the vertical wall just in front of the tube which stops water horizontally flowing out of the tube, is :
[given: density of water =1000kgm3 ]
[28-Jul-2022-Shift-2]
A pressure-pump has a horizontal tube of cross sectional area 10cm2 for the outflow of water at a speed of 20m s. The force exerted on the vertical wall just in front of the tube which stops water horizontally flowing out of the tube, is :
[given: density of water =1000kgm3 ]
[28-Jul-2022-Shift-2]
Q.114 Correct
Q.114 In-correct
Q.114 Unattempt
Consider a cylindrical tank of radius 1m is filled with water. The top surface of water is at 15m from the bottom of the cylinder. There is a hole on the wall of cylinder at a height of 5m from the bottom. A force of 5×105N is applied an the top surface of water using a piston. The speed of ifflux from the hole will be : (given atmospheric pressure PA=1.01×105Pa, density of water ρW=1000kgm3 and gravitational acceleration g=10m s2 )

[28-Jul-2022-Shift-2]
Consider a cylindrical tank of radius 1m is filled with water. The top surface of water is at 15m from the bottom of the cylinder. There is a hole on the wall of cylinder at a height of 5m from the bottom. A force of 5×105N is applied an the top surface of water using a piston. The speed of ifflux from the hole will be : (given atmospheric pressure PA=1.01×105Pa, density of water ρW=1000kgm3 and gravitational acceleration g=10m s2 )

[28-Jul-2022-Shift-2]
Q.115 Correct
Q.115 In-correct
Q.115 Unattempt
Given below are two statements : One is labelled as Assertion (A) and the other is labelled as Reason (R)
Assertion (A): Clothes containing oil or grease stains cannot be cleaned by water wash.
Reason (R): Because the angle of contact between the oil/grease and water is obtuse.
In the light of the above statements, choose the correct answer from the option given below.
[29-Jul-2022-Shift-1]
Given below are two statements : One is labelled as Assertion (A) and the other is labelled as Reason (R)
Assertion (A): Clothes containing oil or grease stains cannot be cleaned by water wash.
Reason (R): Because the angle of contact between the oil/grease and water is obtuse.
In the light of the above statements, choose the correct answer from the option given below.
[29-Jul-2022-Shift-1]
Q.116 Correct
Q.116 In-correct
Q.116 Unattempt
The velocity of a small ball of mass 0.3g and density 8gcc when dropped in a container filled with glycerine becomes constant after some time. If the density of glycerine is 1.3gcc, then the value of viscous force acting on the ball will be x×104N, The value of x is _______. [use g=10ms2 ]
[29-Jul-2022-Shift-2]
The velocity of a small ball of mass 0.3g and density 8gcc when dropped in a container filled with glycerine becomes constant after some time. If the density of glycerine is 1.3gcc, then the value of viscous force acting on the ball will be x×104N, The value of x is _______. [use g=10ms2 ]
[29-Jul-2022-Shift-2]
Q.117 Correct
Q.117 In-correct
Q.117 Unattempt
A wire of length L and radius r is clamped rigidly at one end. When the other end of the wire is pulled by a force F, its length increases by 5cm. Another wire of the same material of length 4L and radius 4r is pulled by a force 4F under same conditions. The increase in length of this wire is cm
[25-Jul-2022-Shift-1]
A wire of length L and radius r is clamped rigidly at one end. When the other end of the wire is pulled by a force F, its length increases by 5cm. Another wire of the same material of length 4L and radius 4r is pulled by a force 4F under same conditions. The increase in length of this wire is cm
[25-Jul-2022-Shift-1]
Q.118 Correct
Q.118 In-correct
Q.118 Unattempt
In an experiment to determine the Young's modulus of wire of a length exactly 1m, the extension in the length of the wire is measured as 0.4mm with an uncertainty of ±0.02mm when a load of 1kg is applied. The diameter of the wire is measured as 0.4mm with an uncertainty of ±0.01mm. The error in the measurement of Young's modulus (Y) is found to be x×1010Nm2. The value of x is ________(. take .g=10ms2)
[26-Jul-2022-Shift-1]
In an experiment to determine the Young's modulus of wire of a length exactly 1m, the extension in the length of the wire is measured as 0.4mm with an uncertainty of ±0.02mm when a load of 1kg is applied. The diameter of the wire is measured as 0.4mm with an uncertainty of ±0.01mm. The error in the measurement of Young's modulus (Y) is found to be x×1010Nm2. The value of x is ________(. take .g=10ms2)
[26-Jul-2022-Shift-1]
Q.119 Correct
Q.119 In-correct
Q.119 Unattempt
The area of cross section of the rope used to lift a load by a crane is 2.5×104m2. The maximum lifting capacity of the crane is 10 metric tons. To increase the lifting capacity of the crane to 25 metric tons, the required area of cross section of the rope should be :
(. take .g=10ms2)
[26-Jul-2022-Shift-2]
The area of cross section of the rope used to lift a load by a crane is 2.5×104m2. The maximum lifting capacity of the crane is 10 metric tons. To increase the lifting capacity of the crane to 25 metric tons, the required area of cross section of the rope should be :
(. take .g=10ms2)
[26-Jul-2022-Shift-2]
Q.120 Correct
Q.120 In-correct
Q.120 Unattempt
A uniform heavy rod of mass 20kg, cross sectional area 0.4m2 and length 20m is hanging from a fixed support. Neglecting the lateral contraction, the elongation in the rod due to its own weight is x×109m. The value of x is ________.
(Given, young modulus Y=2×1011Nm2 and g=10ms2 )
[26-Jul-2022-Shift-2]
A uniform heavy rod of mass 20kg, cross sectional area 0.4m2 and length 20m is hanging from a fixed support. Neglecting the lateral contraction, the elongation in the rod due to its own weight is x×109m. The value of x is ________.
(Given, young modulus Y=2×1011Nm2 and g=10ms2 )
[26-Jul-2022-Shift-2]
Q.121 Correct
Q.121 In-correct
Q.121 Unattempt
A square aluminum (shear modulus is 25×109Nm2 ) slab of side 60cm and thickness 15cm is subjected to a shearing force (on its narrow face) of 18.0×104N. The lower edge is riveted to the floor. The displacement of the upper edge is _______ µm.
[27-Jul-2022-Shift-1]
A square aluminum (shear modulus is 25×109Nm2 ) slab of side 60cm and thickness 15cm is subjected to a shearing force (on its narrow face) of 18.0×104N. The lower edge is riveted to the floor. The displacement of the upper edge is _______ µm.
[27-Jul-2022-Shift-1]
Q.122 Correct
Q.122 In-correct
Q.122 Unattempt
A steel wire of length 3.2m(Ys=2.0×1011Nm2) and a copper wire of length 4.4m(Yc=1.1×1011Nm2), both of radius 1.4mm are connected end to end. When stretched by a load, the net elongation is found to be 1.4mm. The load applied, in Newton, will be: ( Given .π=
22
7
)
[27-Jul-2022-Shift-2]
A steel wire of length 3.2m(Ys=2.0×1011Nm2) and a copper wire of length 4.4m(Yc=1.1×1011Nm2), both of radius 1.4mm are connected end to end. When stretched by a load, the net elongation is found to be 1.4mm. The load applied, in Newton, will be: ( Given .π=
22
7
)
[27-Jul-2022-Shift-2]
Q.123 Correct
Q.123 In-correct
Q.123 Unattempt
In an experiment to determine the Young's modulus, steel wires of five different lengths (1,2,3,4, and 5m) but of same cross section (2mm2) were taken and curves between extension and load were obtained. The slope (extension/load) of the curves were plotted with the wire length and the following graph is obtained. If the Young's modulus of given steel wires is x×1011Nm2, then the value of x is _________.

[27-Jul-2022-Shift-2]
In an experiment to determine the Young's modulus, steel wires of five different lengths (1,2,3,4, and 5m) but of same cross section (2mm2) were taken and curves between extension and load were obtained. The slope (extension/load) of the curves were plotted with the wire length and the following graph is obtained. If the Young's modulus of given steel wires is x×1011Nm2, then the value of x is _________.

[27-Jul-2022-Shift-2]
Q.124 Correct
Q.124 In-correct
Q.124 Unattempt
The force required to stretch a wire of cross-section 1cm2 to double its length will be : (Given Yong's modulus of the wire 2×1011Nm2 )
[28-Jul-2022-Shift-1]
The force required to stretch a wire of cross-section 1cm2 to double its length will be : (Given Yong's modulus of the wire 2×1011Nm2 )
[28-Jul-2022-Shift-1]
Q.125 Correct
Q.125 In-correct
Q.125 Unattempt
A string of area of cross-section 4mm2 and length 0.5m is connected with a rigid body of mass 2kg. The body is rotated in a vertical circular path of radius 0.5m. The body acquires a speed of 5m s at the bottom of the circular path. Strain produced in the string when the body is at the bottom of the circle is ____×105
(use Young's modulus 1011Nm2 and g=10m s2 )
[28-Jul-2022-Shift-2]
A string of area of cross-section 4mm2 and length 0.5m is connected with a rigid body of mass 2kg. The body is rotated in a vertical circular path of radius 0.5m. The body acquires a speed of 5m s at the bottom of the circular path. Strain produced in the string when the body is at the bottom of the circle is ____×105
(use Young's modulus 1011Nm2 and g=10m s2 )
[28-Jul-2022-Shift-2]
Q.126 Correct
Q.126 In-correct
Q.126 Unattempt
If the length of a wire is made double and radius is halved of its respective values. Then, the Young's modulus of the material of the wire will:
[29-Jul-2022-Shift-1]
If the length of a wire is made double and radius is halved of its respective values. Then, the Young's modulus of the material of the wire will:
[29-Jul-2022-Shift-1]
Q.127 Correct
Q.127 In-correct
Q.127 Unattempt
A metal wire of length 0.5m and cross-sectional area 104m2 has breaking stress 5×108Nm2. A block of 10kg is attached at one end of the string and is rotating in a horizontal circle. The maximum linear velocity of block will be _______ ms1
[29-Jul-2022-Shift-2]
A metal wire of length 0.5m and cross-sectional area 104m2 has breaking stress 5×108Nm2. A block of 10kg is attached at one end of the string and is rotating in a horizontal circle. The maximum linear velocity of block will be _______ ms1
[29-Jul-2022-Shift-2]
Q.128 Correct
Q.128 In-correct
Q.128 Unattempt
A unit scale is to be prepared whose length does not change with temperature and remains 20cm, using a bimetallic strip made of brass and iron each of different length. The length of both components would change in such a way that difference between their lengths remains constant. If length of brass is 40cm and length of iron will be cm.(αiron =1.2×105K1 and αbrass =1.8×105K1)
[25-Jul-2022-Shift-1]
A unit scale is to be prepared whose length does not change with temperature and remains 20cm, using a bimetallic strip made of brass and iron each of different length. The length of both components would change in such a way that difference between their lengths remains constant. If length of brass is 40cm and length of iron will be cm.(αiron =1.2×105K1 and αbrass =1.8×105K1)
[25-Jul-2022-Shift-1]
Q.129 Correct
Q.129 In-correct
Q.129 Unattempt
A block of ice of mass 120g at temperature 0C is put in 300g of water at 25C. The ×g of ice melts as the temperature of the water reaches 0C. The value of x is____
[Use specific heat capacity of water =4200Jkg1K1, Latent heat of ice =3.5×105Jkg1 ]
[25-Jul-2022-Shift-2]
A block of ice of mass 120g at temperature 0C is put in 300g of water at 25C. The ×g of ice melts as the temperature of the water reaches 0C. The value of x is____
[Use specific heat capacity of water =4200Jkg1K1, Latent heat of ice =3.5×105Jkg1 ]
[25-Jul-2022-Shift-2]
Q.130 Correct
Q.130 In-correct
Q.130 Unattempt
An ice cube of dimensions 60cm×50cm×20cm is placed in an insulation box of wall thickness 1cm. The box keeping the ice cube at 0C of temperature is brought to a room of temperature 40C The rate of melting of ice is approximately :
(Latent heat of fusion of ice is 3.4×105Jkg1 and thermal conducting of insulation wall is .0.05Wm1C1)
[26-Jul-2022-Shift-2]
An ice cube of dimensions 60cm×50cm×20cm is placed in an insulation box of wall thickness 1cm. The box keeping the ice cube at 0C of temperature is brought to a room of temperature 40C The rate of melting of ice is approximately :
(Latent heat of fusion of ice is 3.4×105Jkg1 and thermal conducting of insulation wall is .0.05Wm1C1)
[26-Jul-2022-Shift-2]
Q.131 Correct
Q.131 In-correct
Q.131 Unattempt
If K1 and K2 are the thermal conductivities, L1 and L2 are the lengths and A1 and A2 are the cross sectional areas of steel and copper rods respectively such that
K2
K1
=9
,
A1
A2
=2
,
L1
L2
=2
. Then, for the arrangement as shown in the figure, the value of temperature T of the steel - copper junction in the steady state will be:

[27-Jul-2022-Shift-1]
If K1 and K2 are the thermal conductivities, L1 and L2 are the lengths and A1 and A2 are the cross sectional areas of steel and copper rods respectively such that
K2
K1
=9
,
A1
A2
=2
,
L1
L2
=2
. Then, for the arrangement as shown in the figure, the value of temperature T of the steel - copper junction in the steady state will be:

[27-Jul-2022-Shift-1]
Q.132 Correct
Q.132 In-correct
Q.132 Unattempt
Read the following statements :
A. When small temperature difference between a liquid and its surrounding is doubled, the rate of loss of heat of the liquid becomes twice.
B. Two bodies P and Q having equal surface areas are maintained at temperature 10C and 20C. The thermal radiation emitted in a given time by P and Q are in the ratio 1:1.15.
C. A Carnot Engine working between 100K and 400K has an efficiency of 75%.
D. When small temperature difference between a liquid and its surrounding is quadrupled, the rate of loss of heat of the liquid becomes twice.
Choose the correct answer from the options given below :
[27-Jul-2022-Shift-1]
Read the following statements :
A. When small temperature difference between a liquid and its surrounding is doubled, the rate of loss of heat of the liquid becomes twice.
B. Two bodies P and Q having equal surface areas are maintained at temperature 10C and 20C. The thermal radiation emitted in a given time by P and Q are in the ratio 1:1.15.
C. A Carnot Engine working between 100K and 400K has an efficiency of 75%.
D. When small temperature difference between a liquid and its surrounding is quadrupled, the rate of loss of heat of the liquid becomes twice.
Choose the correct answer from the options given below :
[27-Jul-2022-Shift-1]
Q.133 Correct
Q.133 In-correct
Q.133 Unattempt
Two metallic wires of identical dimensions are connected in series. If σ1 and σ2 are the conductivities of the these wires respectively, the effective conductivity of the combination is :
[29-Jul-2022-Shift-1]
Two metallic wires of identical dimensions are connected in series. If σ1 and σ2 are the conductivities of the these wires respectively, the effective conductivity of the combination is :
[29-Jul-2022-Shift-1]
Q.134 Correct
Q.134 In-correct
Q.134 Unattempt
Nearly 10% of the power of a 110W light bulb is converted to visible radiation. The change in average intensities of visible radiation, at a distance of 1m from the bulb to a distance of 5m is a×102Wm2. The value of 'a' will be ________.
[29-Jul-2022-Shift-2]
Nearly 10% of the power of a 110W light bulb is converted to visible radiation. The change in average intensities of visible radiation, at a distance of 1m from the bulb to a distance of 5m is a×102Wm2. The value of 'a' will be ________.
[29-Jul-2022-Shift-2]
Q.135 Correct
Q.135 In-correct
Q.135 Unattempt
A uniform metallic wire is elongated by 0.04m when subjected to a linear force F. The elongation, if its length and diameter is doubled and subjected to the same force will be ........... cm
[24 Feb 2021 Shift 2]
A uniform metallic wire is elongated by 0.04m when subjected to a linear force F. The elongation, if its length and diameter is doubled and subjected to the same force will be ........... cm
[24 Feb 2021 Shift 2]
Q.136 Correct
Q.136 In-correct
Q.136 Unattempt
The normal density of a material is ρ and its bulk modulus of elasticity is K. The magnitude of increase in density of material, when a pressure p is applied uniformly on all sides, will be
[26 Feb 2021 Shift 1]
The normal density of a material is ρ and its bulk modulus of elasticity is K. The magnitude of increase in density of material, when a pressure p is applied uniformly on all sides, will be
[26 Feb 2021 Shift 1]
Q.137 Correct
Q.137 In-correct
Q.137 Unattempt
The length of metallic wire is I1 when tension in it is T1. It is I2 when the tension is T2. The original length of the wire will be
[26 Feb 2021 Shift 2]
The length of metallic wire is I1 when tension in it is T1. It is I2 when the tension is T2. The original length of the wire will be
[26 Feb 2021 Shift 2]
Q.138 Correct
Q.138 In-correct
Q.138 Unattempt
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion (A) When a rod lying freely is heated, no thermal stress is developed in it.
Reason (R) On heating, the length of the rod increases.
In the light of the above statements, choose the correct answer from the options given below
[25 Feb 2021 Shift 1]
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion (A) When a rod lying freely is heated, no thermal stress is developed in it.
Reason (R) On heating, the length of the rod increases.
In the light of the above statements, choose the correct answer from the options given below
[25 Feb 2021 Shift 1]
Q.139 Correct
Q.139 In-correct
Q.139 Unattempt
A large number of water drops, each of radius r, combine to have a drop of radius R. If the surface tension is T and mechanical equivalent of heat is J, the rise in heat energy per unit volume will be
[26 Feb 2021 Shift 1]
A large number of water drops, each of radius r, combine to have a drop of radius R. If the surface tension is T and mechanical equivalent of heat is J, the rise in heat energy per unit volume will be
[26 Feb 2021 Shift 1]
Q.140 Correct
Q.140 In-correct
Q.140 Unattempt
If Y,K and η are the values of Young's modulus, bulk modulus and modulus of rigidity of any material respectively. Choose the correct relation for these parameters.
[24feb2021shift1]
If Y,K and η are the values of Young's modulus, bulk modulus and modulus of rigidity of any material respectively. Choose the correct relation for these parameters.
[24feb2021shift1]
Q.141 Correct
Q.141 In-correct
Q.141 Unattempt
A hydraulic press can lift 100kg when a mass 'm' is placed on the smaller piston. It can lift kg when the diameter of the larger piston is increased by 4 times and that of the smaller piston is decreased by 4 times keeping the same mass 'm' on the smaller piston.
[24feb2021shift1]
A hydraulic press can lift 100kg when a mass 'm' is placed on the smaller piston. It can lift kg when the diameter of the larger piston is increased by 4 times and that of the smaller piston is decreased by 4 times keeping the same mass 'm' on the smaller piston.
[24feb2021shift1]
Q.142 Correct
Q.142 In-correct
Q.142 Unattempt
Each side of a box made of metal sheet in cubic shape is ' a ' at room temperature ' T ', the coefficient of linear expansion of the metal sheet is ' α '. The metal sheet is heated uniformly, by a small temperature T, so that its new temperature is T+T. Calculate the increase in the volume of the metal box.
[24feb2021shift1]
Each side of a box made of metal sheet in cubic shape is ' a ' at room temperature ' T ', the coefficient of linear expansion of the metal sheet is ' α '. The metal sheet is heated uniformly, by a small temperature T, so that its new temperature is T+T. Calculate the increase in the volume of the metal box.
[24feb2021shift1]
Q.143 Correct
Q.143 In-correct
Q.143 Unattempt
An object is located at 2km beneath the surface of the water. If the fractional compression
V
V
is 1.36%, the ratio of hydraulic stress to the corresponding hydraulic strain will be ...............
(Take, density of water is 1000kgm3 and g=9.81ms2 )
[17 Mar 2021 Shift 2]
An object is located at 2km beneath the surface of the water. If the fractional compression
V
V
is 1.36%, the ratio of hydraulic stress to the corresponding hydraulic strain will be ...............
(Take, density of water is 1000kgm3 and g=9.81ms2 )
[17 Mar 2021 Shift 2]
Q.144 Correct
Q.144 In-correct
Q.144 Unattempt
Two separate wires A and B are stretched by 2mm and 4mm respectively, when they are subjected to a force of 2N. Assume that both the wires are made up of same material and the radius of wire B is 4 times that of the radius of wire A. The length of the wires A and B are in the ratio of a:b. Then,
a
b
can be expressed as
1
x
, where x is
[18 Mar 2021 Shift 1]
Two separate wires A and B are stretched by 2mm and 4mm respectively, when they are subjected to a force of 2N. Assume that both the wires are made up of same material and the radius of wire B is 4 times that of the radius of wire A. The length of the wires A and B are in the ratio of a:b. Then,
a
b
can be expressed as
1
x
, where x is
[18 Mar 2021 Shift 1]
Q.145 Correct
Q.145 In-correct
Q.145 Unattempt
The pressure acting on a submarine is 3×105Pa at a certain depth. If the depth is doubled, the percentage increase in the pressure acting on the submarine would be (Assume that atmospheric pressure is 1×105Pa, density of water is 103kgm3, g=10ms2 )
[16 Mar 2021 Shift 1]
The pressure acting on a submarine is 3×105Pa at a certain depth. If the depth is doubled, the percentage increase in the pressure acting on the submarine would be (Assume that atmospheric pressure is 1×105Pa, density of water is 103kgm3, g=10ms2 )
[16 Mar 2021 Shift 1]
Q.146 Correct
Q.146 In-correct
Q.146 Unattempt
Consider a water tank as shown in the figure. It's cross-sectional area is 0.4m2. The tank has an opening B near the bottom whose cross-section area is 1cm2. A load of 24kg is applied on the water at the top when the height of the water level is 40cm above the bottom, the velocity of water coming out the opening B is vms1. The value of v, to the nearest integer, is (Take value of g to be 10ms2 )

[18 Mar 2021 Shift 2]
Consider a water tank as shown in the figure. It's cross-sectional area is 0.4m2. The tank has an opening B near the bottom whose cross-section area is 1cm2. A load of 24kg is applied on the water at the top when the height of the water level is 40cm above the bottom, the velocity of water coming out the opening B is vms1. The value of v, to the nearest integer, is (Take value of g to be 10ms2 )

[18 Mar 2021 Shift 2]
Q.147 Correct
Q.147 In-correct
Q.147 Unattempt
What will be the nature of flow of water from a circular tap, when its flow rate increased from 0.18L/min to 0.48L/min ? The radius of the tap and viscosity of water are 0.5cm and 103Pas, respectively.
(Density of water =103kg/m3 )
[16 Mar 2021 Shift 2]
What will be the nature of flow of water from a circular tap, when its flow rate increased from 0.18L/min to 0.48L/min ? The radius of the tap and viscosity of water are 0.5cm and 103Pas, respectively.
(Density of water =103kg/m3 )
[16 Mar 2021 Shift 2]
Q.148 Correct
Q.148 In-correct
Q.148 Unattempt
When two soap bubbles of radii a and b(b>a) coalesce, the radius of curvature of common surface is
[17 Mar 2021 Shift 1]
When two soap bubbles of radii a and b(b>a) coalesce, the radius of curvature of common surface is
[17 Mar 2021 Shift 1]
Q.149 Correct
Q.149 In-correct
Q.149 Unattempt
Two wires of same length and radius are joined end to end and loaded. The Young's modulii of the materials of the two wires are Y1 and Y2. The combination behaves as a single wire then its Young's modulus is :
[25 Jul 2021 Shift 1]
Two wires of same length and radius are joined end to end and loaded. The Young's modulii of the materials of the two wires are Y1 and Y2. The combination behaves as a single wire then its Young's modulus is :
[25 Jul 2021 Shift 1]
Q.150 Correct
Q.150 In-correct
Q.150 Unattempt
The length of a metal wire is l1, when the tension in it is T1 and is l2 when the tension is T2. The natural length of the wire is :
[20 Jul 2021 Shift 2]
The length of a metal wire is l1, when the tension in it is T1 and is l2 when the tension is T2. The natural length of the wire is :
[20 Jul 2021 Shift 2]
Q.151 Correct
Q.151 In-correct
Q.151 Unattempt
The value of tension in a long thin metal wire has been changed from T1 to T2. The lengths of the metal wire at two different values of tension T1 andT2 are l1 and l2 respectively. The actual length of the metal wire is :
[20 Jul 2021 Shift 1]
The value of tension in a long thin metal wire has been changed from T1 to T2. The lengths of the metal wire at two different values of tension T1 andT2 are l1 and l2 respectively. The actual length of the metal wire is :
[20 Jul 2021 Shift 1]
Q.152 Correct
Q.152 In-correct
Q.152 Unattempt
A stone of mass 20g is projected from a rubber catapult of length 0.1m and area of cross section106m2 stretched by an amount 0.04m. The velocity of the projected stone is __________ ms
(Young's modulus of rubber =0.5×109Nm2 )
[27 Jul 2021 Shift 1]
A stone of mass 20g is projected from a rubber catapult of length 0.1m and area of cross section106m2 stretched by an amount 0.04m. The velocity of the projected stone is __________ ms
(Young's modulus of rubber =0.5×109Nm2 )
[27 Jul 2021 Shift 1]
Q.153 Correct
Q.153 In-correct
Q.153 Unattempt
The area of cross-section of a railway track is 0.01m2. The temperature variation is 10°C. Coefficient of linear expansion of material of track is 105°C. The energy stored per meter in the track is _______ Jm.
(Young's modulus of material of track is 1011Nm2 )
[22 Jul 2021 Shift 2]
The area of cross-section of a railway track is 0.01m2. The temperature variation is 10°C. Coefficient of linear expansion of material of track is 105°C. The energy stored per meter in the track is _______ Jm.
(Young's modulus of material of track is 1011Nm2 )
[22 Jul 2021 Shift 2]
Q.154 Correct
Q.154 In-correct
Q.154 Unattempt
A light cylindrical vessel is kept on a horizontal surface. Area of base is A. A hole of cross sectional area 'a' is made just at its bottom side.
The minimum coefficient of friction necessary to prevent sliding the vessel due to the impact force of the emerging liquid is (a < < A) :

[27 Jul 2021 Shift 1]
A light cylindrical vessel is kept on a horizontal surface. Area of base is A. A hole of crosssectional area 'a' is made just at its bottom side.
The minimum coefficient of friction necessary to prevent sliding the vessel due to the impact force of the emerging liquid is (a < < A) :

[27 Jul 2021 Shift 1]
Q.155 Correct
Q.155 In-correct
Q.155 Unattempt
A raindrop with radius R=0.2mm falls from a cloud at a height h=2000m above the ground.
Assume that the drop is spherical throughout its fall and the force of buoyance may be neglected, then the terminal speed attained by the raindrop is :
[Density of water fw=1000kgm3 and Density of air fa=1.2kgm3,g=10ms2
Coefficient of viscosity of air =1.8×105Nsm2 ]
[27 Jul 2021 Shift 2]
A raindrop with radius R=0.2mm falls from a cloud at a height h=2000m above the ground.
Assume that the drop is spherical throughout its fall and the force of buoyance may be neglected, then the terminal speed attained by the raindrop is :
[Density of water fw=1000kgm3 and Density of air fa=1.2kgm3,g=10ms2
Coefficient of viscosity of air =1.8×105Nsm2 ]
[27 Jul 2021 Shift 2]
Q.156 Correct
Q.156 In-correct
Q.156 Unattempt
The water is filled upto height of 12 m in a tank having vertical sidewalls. A hole is made in one of the walls at a depth 'h' below the water level. The value of 'h' for which the emerging stream of water strikes the ground at the maximum range is ___ m.
[27 Jul 2021 Shift 2]
The water is filled upto height of 12 m in a tank having vertical sidewalls. A hole is made in one of the walls at a depth 'h' below the water level. The value of 'h' for which the emerging stream of water strikes the ground at the maximum range is ___ m.
[27 Jul 2021 Shift 2]
Q.157 Correct
Q.157 In-correct
Q.157 Unattempt
Two spherical soap bubbles of radii r1 and r2 in vacuum combine under isothermal conditions. The resulting bubble has a radius equal to :
[25 Jul 2021 Shift 2]
Two spherical soap bubbles of radii r1 and r2 in vacuum combine under isothermal conditions. The resulting bubble has a radius equal to :
[25 Jul 2021 Shift 2]
Q.158 Correct
Q.158 In-correct
Q.158 Unattempt
Two small drops of mercury each of radius R coalesce to form a single large drop. The ratio of total surface energy before and after the change is :
[20 Jul 2021 Shift 2]
Two small drops of mercury each of radius R coalesce to form a single large drop. The ratio of total surface energy before and after the change is :
[20 Jul 2021 Shift 2]
Q.159 Correct
Q.159 In-correct
Q.159 Unattempt
A uniform heavy rod of weight 10kgms2, cross-sectional area 100cm2 and length 20cm is hanging from a fixed support. Young's modulus of the material of the rod is 2×1011Nm2. Neglecting the lateral contraction, find the elongation of rod due to its own weight.
[31 Aug 2021 Shift 1]
A uniform heavy rod of weight 10kgms2, cross-sectional area 100cm2 and length 20cm is hanging from a fixed support. Young's modulus of the material of the rod is 2×1011Nm2. Neglecting the lateral contraction, find the elongation of rod due to its own weight.
[31 Aug 2021 Shift 1]
Q.160 Correct
Q.160 In-correct
Q.160 Unattempt
Section B : Numerical Type Questions
When a rubber ball is taken to a depth of ....... m in deep sea, its volume decreases by 0.5%. (The bulk modulus of rubber =9.8×108Nm2.
Density of sea water =103kgm3, g=9.8ms2)
[31 Aug 2021 Shift 1]
Section B : Numerical Type Questions
When a rubber ball is taken to a depth of ....... m in deep sea, its volume decreases by 0.5%. (The bulk modulus of rubber =9.8×108Nm2.
Density of sea water =103kgm3, g=9.8ms2)
[31 Aug 2021 Shift 1]
Q.161 Correct
Q.161 In-correct
Q.161 Unattempt
Four identical hollow cylindrical columns of mild steel support a big structure of mass 50×103kg. The inner and outer radii of each column are 50cm and 100cm, respectively. Assuming, uniform local distribution, calculate the compression strain of each column.
[Use, Y=2.0×1011Pa,g=9.8ms2].
[31 Aug 2021 Shift 2]
Four identical hollow cylindrical columns of mild steel support a big structure of mass 50×103kg. The inner and outer radii of each column are 50cm and 100cm, respectively. Assuming, uniform local distribution, calculate the compression strain of each column.
[Use, Y=2.0×1011Pa,g=9.8ms2].
[31 Aug 2021 Shift 2]
Q.162 Correct
Q.162 In-correct
Q.162 Unattempt
Wires W1 and W2 are made of same material having the breaking stress of 1.25×109Nm2. W1 and W2 have cross-sectional area of 8×107m2 and 4×107m2, respectively. Masses of 20kg and 10kg hang from them as shown in the figure. The maximum mass that can be placed in the pan without breaking the wires is .......... kg.
(Use, g=10ms2)

[27 Aug 2021 Shift 2]
Wires W1 and W2 are made of same material having the breaking stress of 1.25×109Nm2. W1 and W2 have cross-sectional area of 8×107m2 and 4×107m2, respectively. Masses of 20kg and 10kg hang from them as shown in the figure. The maximum mass that can be placed in the pan without breaking the wires is .......... kg.
(Use, g=10ms2)

[27 Aug 2021 Shift 2]
Q.163 Correct
Q.163 In-correct
Q.163 Unattempt
Two blocks of masses 3kg and 5kg are connected by a metal wire going over a smooth pulley. The breaking stress of the metal is (
24
π
)
×102Nm2
. What is the minimum radius of the wire?
(Take, g=10ms2 )

[26 Aug 2021 Shift 2]
Two blocks of masses 3kg and 5kg are connected by a metal wire going over a smooth pulley. The breaking stress of the metal is (
24
π
)
×102Nm2
. What is the minimum radius of the wire?
(Take, g=10ms2 )

[26 Aug 2021 Shift 2]
Q.164 Correct
Q.164 In-correct
Q.164 Unattempt
In Millikan's oil drop experiment, what is viscous force acting on an uncharged drop of radius 2.0×105m and density 1.2×103kgm3 ? Take viscosity of liquid =1.8×105Nsm2. (Neglect buoyancy due to air).
[27 Aug 2021 Shift 1]
In Millikan's oil drop experiment, what is viscous force acting on an uncharged drop of radius 2.0×105m and density 1.2×103kgm3 ? Take viscosity of liquid =1.8×105Nsm2. (Neglect buoyancy due to air).
[27 Aug 2021 Shift 1]
Q.165 Correct
Q.165 In-correct
Q.165 Unattempt
Two narrow bores of diameter 5.0mm and 8.0mm are joined together to form a U-shaped tube open at both ends. If this U-tube contains water, what is the difference in the level of two limbs of the tube.
[Take surface tension of water T=7.3×102Nm1, angle of contact =0,g=10ms2 and density of water =1.0×103kgm3 ]
[26 Aug 2021 Shift 1]
Two narrow bores of diameter 5.0mm and 8.0mm are joined together to form a U-shaped tube open at both ends. If this U-tube contains water, what is the difference in the level of two limbs of the tube.
[Take surface tension of water T=7.3×102Nm1, angle of contact =0,g=10ms2 and density of water =1.0×103kgm3 ]
[26 Aug 2021 Shift 1]
Q.166 Correct
Q.166 In-correct
Q.166 Unattempt
A soap bubble of radius 3cm is formed inside the another soap bubble of radius 6cm. The radius of an equivalent soap bubble which has the same excess pressure as inside the smaller bubble with respect to the atmospheric pressure is .......... cm.
[26 Aug 2021 Shift 1]
A soap bubble of radius 3cm is formed inside the another soap bubble of radius 6cm. The radius of an equivalent soap bubble which has the same excess pressure as inside the smaller bubble with respect to the atmospheric pressure is .......... cm.
[26 Aug 2021 Shift 1]
Q.167 Correct
Q.167 In-correct
Q.167 Unattempt
A steel rod with Y=2.0×1011Nm2
and α=105°C1 of length 4m and area of cross-section 10cm2 is heated from 0°C to 400°C without being allowed to extend. The tension produced in the rod is x×105N, where the value of x is .......... .
[1 Sep 2021 Shift 2]
A steel rod with Y=2.0×1011Nm2
and α=105°C1 of length 4m and area of cross-section 10cm2 is heated from 0°C to 400°C without being allowed to extend. The tension produced in the rod is x×105N, where the value of x is .......... .
[1 Sep 2021 Shift 2]
Q.168 Correct
Q.168 In-correct
Q.168 Unattempt
A body of mass m=10kg is attached to one end of a wire of length 0.3m. The maximum angular speed (in rads1 ) with which it can be rotated about its other end in space station is (Breaking stress of wire =4.8×107Nm2 and area of cross section of the wire =102cm2 ) is ______.
[9 Jan 2020 I]
A body of mass m=10kg is attached to one end of a wire of length 0.3m. The maximum angular speed (in rads1 ) with which it can be rotated about its other end in space station is (Breaking stress of wire =4.8×107Nm2 and area of cross section of the wire =102cm2 ) is ______.
[9 Jan 2020 I]
Q.169 Correct
Q.169 In-correct
Q.169 Unattempt
Two steel wires having same length are suspended from a ceiling under the same load. If the ratio of their energy stored per unit volume is 1:4, the ratio of their diameters is:
[9 Jan 2020 II]
Two steel wires having same length are suspended from a ceiling under the same load. If the ratio of their energy stored per unit volume is 1:4, the ratio of their diameters is:
[9 Jan 2020 II]
Q.170 Correct
Q.170 In-correct
Q.170 Unattempt
Three containers C1,C2 and C3 have water at different temperatures. The table below shows the final temperature T when different amounts of water (given in liters) are taken from each container and mixed (assume no loss of heat during the process)

The value of θ (in °C to the nearest integer) is______.
[8 Jan. 2020 II]
Three containers C1,C2 and C3 have water at different temperatures. The table below shows the final temperature T when different amounts of water (given in liters) are taken from each container and mixed (assume no loss of heat during the process)

The value of θ (in °C to the nearest integer) is______.
[8 Jan. 2020 II]
Q.171 Correct
Q.171 In-correct
Q.171 Unattempt
A leak proof cylinder of length 1m, made of a metal which has very low coefficient of expansion is floating vertically in water at 0°C such that its height above the water surface is 20cm. When the temperature of water is increased to 4°C, the height of the cylinder above the water surface becomes 21cm. The density of water at T=4°C, relative to the density at T=0°C is close to:
[8 Jan 2020 (I)]
A leak proof cylinder of length 1m, made of a metal which has very low coefficient of expansion is floating vertically in water at 0°C such that its height above the water surface is 20cm. When the temperature of water is increased to 4°C, the height of the cylinder above the water surface becomes 21cm. The density of water at T=4°C, relative to the density at T=0°C is close to:
[8 Jan 2020 (I)]
Q.172 Correct
Q.172 In-correct
Q.172 Unattempt
Consider a solid sphere of radius R and mass densityρ(r)=ρ0(1
r2
R2
)
,0<rR.
The minimum density of a liquid in which it will float is:
[8 Jan 2020 (I)]
Consider a solid sphere of radius R and mass densityρ(r)=ρ0(1
r2
R2
)
,0<rR.
The minimum density of a liquid in which it will float is:
[8 Jan 2020 (I)]
Q.173 Correct
Q.173 In-correct
Q.173 Unattempt
Two liquids of densities ρ1 and ρ2(ρ2=2ρ1) are filled up behind a square wall of side 10m as shown in figure. Each liquid has a height of 5m. The ratio of the forces due to these liquids exerted on upper part MN to that at the lower part NO is (Assume that the liquids are not mixing):
[8 Jan 2020 (II)]

Two liquids of densities ρ1 and ρ2(ρ2=2ρ1) are filled up behind a square wall of side 10m as shown in figure. Each liquid has a height of 5m. The ratio of the forces due to these liquids exerted on upper part MN to that at the lower part NO is (Assume that the liquids are not mixing):
[8 Jan 2020 (II)]
Q.174 Correct
Q.174 In-correct
Q.174 Unattempt
Water flows in a horizontal tube (see figure). The pressure of water changes by 700Nm2 between A and B where the area of cross section are 40cm2 and 20cm2, respectively. Find the rate of flow of water through the tube. (density of water =1000kgm3)

[9 Jan. 2020 (I)]
Water flows in a horizontal tube (see figure). The pressure of water changes by 700Nm2 between A and B where the area of cross section are 40cm2 and 20cm2, respectively. Find the rate of flow of water through the tube. (density of water =1000kgm3)

[9 Jan. 2020 (I)]
Q.175 Correct
Q.175 In-correct
Q.175 Unattempt
An ideal fluid flows (laminar flow) through a pipe of nonuniform diameter. The maximum and minimum diameters of the pipes are 6.4cm and 4.8cm, respectively. The ratio of the minimum and the maximum velocities of fluid in this pipe is:
[7 Jan. 2020 (II)]
An ideal fluid flows (laminar flow) through a pipe of nonuniform diameter. The maximum and minimum diameters of the pipes are 6.4cm and 4.8cm, respectively. The ratio of the minimum and the maximum velocities of fluid in this pipe is:
[7 Jan. 2020 (II)]
Q.176 Correct
Q.176 In-correct
Q.176 Unattempt
A small spherical droplet of density d is floating exactly halfimmersed in a liquid of density ρ and surface tension T. The radius of the droplet is (take note that the surface tension applies an upward force on the droplet):
[9 Jan. 2020 (II)]
A small spherical droplet of density d is floating exactly halfimmersed in a liquid of density ρ and surface tension T. The radius of the droplet is (take note that the surface tension applies an upward force on the droplet):
[9 Jan. 2020 (II)]
Q.177 Correct
Q.177 In-correct
Q.177 Unattempt
A non-isotropic solid metal cube has coefficients of linear expansion as: 5×105°C along the x-axis and 5×106°C along the y and the z-axis. If the coefficient of volume expansion of the solid is C×106°C then the value of C is _______.
[NA 7 Jan. 2020 I]
A non-isotropic solid metal cube has coefficients of linear expansion as: 5×105°C along the x-axis and 5×106°C along the y and the z-axis. If the coefficient of volume expansion of the solid is C×106°C then the value of C is _______.
[NA 7 Jan. 2020 I]
Q.178 Correct
Q.178 In-correct
Q.178 Unattempt
M grams of steam at 100°C is mixed with 200 g of ice at its melting point in a thermally insulated container. If it produces liquid water at 40°C [heat of vaporization of water is 540 cal/ g and heat of fusion of ice is 80 cal/g], the value of M is ________.
[NA 7 Jan. 2020 II]
M grams of steam at 100°C is mixed with 200 g of ice at its melting point in a thermally insulated container. If it produces liquid water at 40°C [heat of vaporization of water is 540 cal/ g and heat of fusion of ice is 80 cal/g], the value of M is ________.
[NA 7 Jan. 2020 II]
Q.179 Correct
Q.179 In-correct
Q.179 Unattempt
If the potential energy between two molecules is given by U=
A
r6
+
B
r12
,
then at equilibrium, separation between molecules, and the potential energy are:
[Sep. 06, 2020 (I)]
If the potential energy between two molecules is given by U=
A
r6
+
B
r12
,
then at equilibrium, separation between molecules, and the potential energy are:
[Sep. 06, 2020 (I)]
Q.180 Correct
Q.180 In-correct
Q.180 Unattempt
A hollow spherical shell at outer radius R floats just submerged under the water surface. The inner radius of the shell is r. If the specific gravity of the shell material is
27
8
w.r.t water, the value of r is:
[5 Sep. 2020 (I)]
A hollow spherical shell at outer radius R floats just submerged under the water surface. The inner radius of the shell is r. If the specific gravity of the shell material is
27
8
w.r.t water, the value of r is:
[5 Sep. 2020 (I)]
Q.181 Correct
Q.181 In-correct
Q.181 Unattempt
An air bubble of radius 1cm in water has an upward acceleration 9.8cms2. The density of water is 1gm cm3 and water offers negligible drag force on the bubble. The mass of the bubble is (g=980cms2)
[4 Sep. 2020 (I)]
An air bubble of radius 1cm in water has an upward acceleration 9.8cms2. The density of water is 1gm cm3 and water offers negligible drag force on the bubble. The mass of the bubble is (g=980cms2)
[4 Sep. 2020 (I)]
Q.182 Correct
Q.182 In-correct
Q.182 Unattempt
Two identical cylindrical vessels are kept on the ground and each contain the same liquid of density d. The area of the base of both vessels is S but the height of liquid in one vessel is x1 and in the other, x2. When both cylinders are connected through a pipe of negligible volume very close to the bottom, the liquid flows from one vessel to the other until it comes to equilibrium at a new height. The change in energy of the system in the process is:
[4 Sep. 2020 (II)]
Two identical cylindrical vessels are kept on the ground and each contain the same liquid of density d. The area of the base of both vessels is S but the height of liquid in one vessel is x1 and in the other, x2. When both cylinders are connected through a pipe of negligible volume very close to the bottom, the liquid flows from one vessel to the other until it comes to equilibrium at a new height. The change in energy of the system in the process is:
[4 Sep. 2020 (II)]
Q.183 Correct
Q.183 In-correct
Q.183 Unattempt
A fluid is flowing through a horizontal pipe of varying crosssection, with speed vms1 at a point where the pressure is P Pascal. At another point where pressure is
P
2
Pascal its speed is Vms1. If the density of the fluid is ρkgm3 and the flow is streamline, then V is equal to :
[6 Sep. 2020 (II)]
A fluid is flowing through a horizontal pipe of varying crosssection, with speed vms1 at a point where the pressure is P Pascal. At another point where pressure is
P
2
Pascal its speed is Vms1. If the density of the fluid is ρkgm3 and the flow is streamline, then V is equal to :
[6 Sep. 2020 (II)]
Q.184 Correct
Q.184 In-correct
Q.184 Unattempt
In an experiment to verify Stokes law, a small spherical ball of radius r and density ρ falls under gravity through a distance h in air before entering a tank of water. If the terminal velocity of the ball inside water is same as its velocity just before entering the water surface, then the value of h is proportional to :
(ignore viscosity of air)
[5 Sep. 2020 (II)]
In an experiment to verify Stokes law, a small spherical ball of radius r and density ρ falls under gravity through a distance h in air before entering a tank of water. If the terminal velocity of the ball inside water is same as its velocity just before entering the water surface, then the value of h is proportional to :
(ignore viscosity of air)
[5 Sep. 2020 (II)]
Q.185 Correct
Q.185 In-correct
Q.185 Unattempt
When a long glass capillary tube of radius 0.015cm is dipped in a liquid, the liquid rises to a height of 15cm within it. If the contact angle between the liquid and glass to close to 0°, the surface tension of the liquid, in milli Newton m1, is [ρ(liquid) =900kgm3,g=10ms2]
(Give answer in closest integer) _______.
[NA 3 Sep. 2020 (I)]
When a long glass capillary tube of radius 0.015cm is dipped in a liquid, the liquid rises to a height of 15cm within it. If the contact angle between the liquid and glass to close to 0°, the surface tension of the liquid, in milli Newton m1, is [ρ(liquid) =900kgm3,g=10ms2]
(Give answer in closest integer) _______.
[NA 3 Sep. 2020 (I)]
Q.186 Correct
Q.186 In-correct
Q.186 Unattempt
Pressure inside two soap bubbles are 1.01 and 1.02 atmosphere, respectively. The ratio of their volumes is :
[3 Sep. 2020 (I)]
Pressure inside two soap bubbles are 1.01 and 1.02 atmosphere, respectively. The ratio of their volumes is :
[3 Sep. 2020 (I)]
Q.187 Correct
Q.187 In-correct
Q.187 Unattempt
A capillary tube made of glass of radius 0.15mm is dipped vertically in a beaker filled with methylene iodide (surface tension =0.05Nm1, density left.=667kgm3) which rises to height h in the tube . It is observed that the two tangents drawn from liquid-glass interfaces (from opp. sides of the capillary) make an angle of 60° with one another. Then h is close to (g=10ms2).
[2 Sep. 2020 (II)]
A capillary tube made of glass of radius 0.15mm is dipped vertically in a beaker filled with methylene iodide (surface tension =0.05Nm1, density left.=667kgm3) which rises to height h in the tube . It is observed that the two tangents drawn from liquid-glass interfaces (from opp. sides of the capillary) make an angle of 60° with one another. Then h is close to (g=10ms2).
[2 Sep. 2020 (II)]
Q.188 Correct
Q.188 In-correct
Q.188 Unattempt
Two different wires having lengths L1 and L2, and respective temperature coefficient of linear expansion α1 and α2, are joined end-to-end. Then the effective temperature coefficient of linear expansion is :
[Sep. 05,2020 (II)]
Two different wires having lengths L1 and L2, and respective temperature coefficient of linear expansion α1 and α2, are joined end-to-end. Then the effective temperature coefficient of linear expansion is :
[Sep. 05,2020 (II)]
Q.189 Correct
Q.189 In-correct
Q.189 Unattempt
A bakelite beaker has volume capacity of 500cc at 30°C. When it is partially filled with Vm volume (at 30°C) of mercury, it is found that the unfilled volume of the beaker remains constant as temperature is varied. If γ(beaker) =6× 106°C1 and γ(mercury )=1.5×104°C1, where gamma is the coefficient of volume expansion, then Vm (in cc) is close to __________.
[NA Sep. 03,2020 (I)]
A bakelite beaker has volume capacity of 500cc at 30°C. When it is partially filled with Vm volume (at 30°C) of mercury, it is found that the unfilled volume of the beaker remains constant as temperature is varied. If γ(beaker) =6× 106°C1 and γ(mercury )=1.5×104°C1, where gamma is the coefficient of volume expansion, then Vm (in cc) is close to __________.
[NA Sep. 03,2020 (I)]
Q.190 Correct
Q.190 In-correct
Q.190 Unattempt
When the temperature of a metal wire is increased from 0°C to 10°C, its length increased by 0.02%. The percentage change in its mass density will be closest to :
[Sep. 02, 2020 (II)]
When the temperature of a metal wire is increased from 0°C to 10°C, its length increased by 0.02%. The percentage change in its mass density will be closest to :
[Sep. 02, 2020 (II)]
Q.191 Correct
Q.191 In-correct
Q.191 Unattempt
Three rods of identical cross-section and lengths are made of three different materials of thermal conductivity K1,K2 and K3, respectively. They are joined together at their ends to make a long rod (see figure). One end of the long rod is maintained at 100°C and the other at 0°C (see figure). If the joints of the rod are at 70°C and 20°C in steady state and there is no loss of energy from the surface of the rod, the correct relationship between K1,K2 and K3 is:

[Sep. 06, 2020 (II)]
Three rods of identical cross-section and lengths are made of three different materials of thermal conductivity K1,K2 and K3, respectively. They are joined together at their ends to make a long rod (see figure). One end of the long rod is maintained at 100°C and the other at 0°C (see figure). If the joints of the rod are at 70°C and 20°C in steady state and there is no loss of energy from the surface of the rod, the correct relationship between K1,K2 and K3 is:

[Sep. 06, 2020 (II)]
Q.192 Correct
Q.192 In-correct
Q.192 Unattempt
A bullet of mass 5 g, travelling with a speed of 210 m/s, strikes a fixed wooden target. One half of its kinetics energy is converted into heat in the bullet while the other half is converted into heat in the wood. The rise of temperature of the bullet if the specific heat of its material is 0.030 cal/(g – ºC) (1 cal = 4.2×107 ergs) close to :
[Sep. 05, 2020 (I)]
A bullet of mass 5 g, travelling with a speed of 210 m/s, strikes a fixed wooden target. One half of its kinetics energy is converted into heat in the bullet while the other half is converted into heat in the wood. The rise of temperature of the bullet if the specific heat of its material is 0.030 cal/(g – ºC) (1 cal = 4.2×107 ergs) close to :
[Sep. 05, 2020 (I)]
Q.193 Correct
Q.193 In-correct
Q.193 Unattempt
The specific heat of water =4200Jkg1K1 and the latent heat of ice =3.4×105Jkg1.100 grams of ice at 0°C is placed in 200g of water at 25°C. The amount of ice that will melt as the temperature of water reaches 0°C is close to (in grams):
[Sep. 04, 2020 (I)]
The specific heat of water =4200Jkg1K1 and the latent heat of ice =3.4×105Jkg1.100 grams of ice at 0°C is placed in 200g of water at 25°C. The amount of ice that will melt as the temperature of water reaches 0°C is close to (in grams):
[Sep. 04, 2020 (I)]
Q.194 Correct
Q.194 In-correct
Q.194 Unattempt
A calorimter of water equivalent 20g contains 180g of water at 25°C. ' m ' grams of steam at 100°C is mixed in it till the temperature of the mixture is 31°C. The value of ' m ' is close to (Latent heat of water =540 cal g1, specific heat of water =1 cal g1°C1)
[Sep. 03, 2020 (II)]
A calorimter of water equivalent 20g contains 180g of water at 25°C. ' m ' grams of steam at 100°C is mixed in it till the temperature of the mixture is 31°C. The value of ' m ' is close to (Latent heat of water =540 cal g1, specific heat of water =1 cal g1°C1)
[Sep. 03, 2020 (II)]
Q.195 Correct
Q.195 In-correct
Q.195 Unattempt
A metallic sphere cools from 50°C to 40°C in 300 s. If atmospheric temperature around is 20°C, then the sphere's temperature after the next 5 minutes will be close to :
[Sep. 03, 2020 (II)]
A metallic sphere cools from 50°C to 40°C in 300 s. If atmospheric temperature around is 20°C, then the sphere's temperature after the next 5 minutes will be close to :
[Sep. 03, 2020 (II)]
Q.196 Correct
Q.196 In-correct
Q.196 Unattempt
A load of mass Mkg is suspended from a steel wire of length 2m and radius 1.0mm in Searle's apparatus experiment. The increase in length produced in the wire is 4.0mm. Now the load is fully immersed in a liquid of relative density 2 . The relative density of the material of load is 8 . The new value of increase in length of the steel wire is :
[12 Jan. 2019 (II)]
A load of mass Mkg is suspended from a steel wire of length 2m and radius 1.0mm in Searle's apparatus experiment. The increase in length produced in the wire is 4.0mm. Now the load is fully immersed in a liquid of relative density 2 . The relative density of the material of load is 8 . The new value of increase in length of the steel wire is :
[12 Jan. 2019 (II)]
Q.197 Correct
Q.197 In-correct
Q.197 Unattempt
A soap bubble, blown by a mechanical pump at the mouth of a tube, increases in volume, with time, at a constant rate. The graph that correctly depicts the time dependence of pressure inside the bubble is given by:
[12 Jan. 2019 (II)]
A soap bubble, blown by a mechanical pump at the mouth of a tube, increases in volume, with time, at a constant rate. The graph that correctly depicts the time dependence of pressure inside the bubble is given by:
[12 Jan. 2019 (II)]
Q.198 Correct
Q.198 In-correct
Q.198 Unattempt
A liquid of density ρ is coming out of a hose pipe of radius a with horizontal speed v and hits a mesh. 50% of the liquid passes through the mesh unaffected. 25% looses all of its momentum and 25% comes back with the
[11 Jan. 2019 (I)]
A liquid of density ρ is coming out of a hose pipe of radius a with horizontal speed v and hits a mesh. 50% of the liquid passes through the mesh unaffected. 25% looses all of its momentum and 25% comes back with the
[11 Jan. 2019 (I)]
Q.199 Correct
Q.199 In-correct
Q.199 Unattempt
Water flows into a large tank with flat bottom at the rate of 104m3s(1) Water is also leaking out of a hole of area 1cm2 at its bottom. If the height of the water in the tank remains steady, then this height is:
[10 Jan. 2019 I]
Water flows into a large tank with flat bottom at the rate of 104m3s(1) Water is also leaking out of a hole of area 1cm2 at its bottom. If the height of the water in the tank remains steady, then this height is:
[10 Jan. 2019 I]
Q.200 Correct
Q.200 In-correct
Q.200 Unattempt
The top of a water tank is open to air and its water lavel is maintained. It is giving out 0.74m3 water per minute through a circular opening of 2 cm radius in its wall. The depth of the centre of the opening from the level of water in the tank is close to:
[9 Jan. 2019 (II)]
The top of a water tank is open to air and its water lavel is maintained. It is giving out 0.74m3 water per minute through a circular opening of 2 cm radius in its wall. The depth of the centre of the opening from the level of water in the tank is close to:
[9 Jan. 2019 (II)]
Q.201 Correct
Q.201 In-correct
Q.201 Unattempt
Two rods A and B of identical dimensions are at temperature 30°C. If A is heated upto 180°C and B upto T°C, then the new lengths are the same. If the ratio of the coefficients of linear expansion of A and B is 4 : 3, then the value of T is :
[11 Jan. 2019 II]
Two rods A and B of identical dimensions are at temperature 30°C. If A is heated upto 180°C and B upto T°C, then the new lengths are the same. If the ratio of the coefficients of linear expansion of A and B is 4 : 3, then the value of T is :
[11 Jan. 2019 II]
Q.202 Correct
Q.202 In-correct
Q.202 Unattempt
A thermometer graduated according to a linear scale reads a value x0 when in contact with boiling water, and x03 when in contact with ice. What is the temperature of an object in °C, if this thermometer in the contact with the object reads x02?
[11 Jan. 2019 II]
A thermometer graduated according to a linear scale reads a value x0 when in contact with boiling water, and x03 when in contact with ice. What is the temperature of an object in °C, if this thermometer in the contact with the object reads x02?
[11 Jan. 2019 II]
Q.203 Correct
Q.203 In-correct
Q.203 Unattempt
A rod, of length L at room temperature and uniform area of cross section A, is made of a metal having coefficient of linear expansion α°C. It is observed that an external compressive force F, is applied on each of its ends, prevents any change in the length of the rod, when its temperature rises by ΔTK. Young's modulus, Y, for this metal is:
[9 Jan. 2019 I]
A rod, of length L at room temperature and uniform area of cross section A, is made of a metal having coefficient of linear expansion α°C. It is observed that an external compressive force F, is applied on each of its ends, prevents any change in the length of the rod, when its temperature rises by ΔTK. Young's modulus, Y, for this metal is:
[9 Jan. 2019 I]
Q.204 Correct
Q.204 In-correct
Q.204 Unattempt
A cylinder of radius R is surrounded by a cylindrical shell of inner radius R and outer radius 2R. The thermal conductivity of the material of the inner cylinder is K1 and that of the outer cylinder is K2. Assuming no loss of heat, the effective thermal conductivity of the system for heat flowing along the length of the cylinder is:
[12 Jan. 2019 I]
A cylinder of radius R is surrounded by a cylindrical shell of inner radius R and outer radius 2R. The thermal conductivity of the material of the inner cylinder is K1 and that of the outer cylinder is K2. Assuming no loss of heat, the effective thermal conductivity of the system for heat flowing along the length of the cylinder is:
[12 Jan. 2019 I]
Q.205 Correct
Q.205 In-correct
Q.205 Unattempt
Ice at –20°C is added to 50 g of water at 40°C, When the temperature of the mixture reaches 0°C, it is found that 20 g of ice is still unmelted. The amount of ice added to the water was close to
(Specific heat of water = 4.2J/g/°C
Specific heat of Ice = 2.1 J/g/°C
Heat of fusion of water at 0°C = 334J/g)
[11 Jan. 2019 I]
Ice at –20°C is added to 50 g of water at 40°C, When the temperature of the mixture reaches 0°C, it is found that 20 g of ice is still unmelted. The amount of ice added to the water was close to
(Specific heat of water = 4.2J/g/°C
Specific heat of Ice = 2.1 J/g/°C
Heat of fusion of water at 0°C = 334J/g)
[11 Jan. 2019 I]
Q.206 Correct
Q.206 In-correct
Q.206 Unattempt
When 100 g of a liquid A at 100°C is added to 50 g of a liquid B at temperature 75°C, the temperature of the mixture becomes 90°C. The temperature of the mixture, if 100 g of liquid A at 100°C is added to 50 g of liquid B at 50°C, will be :
[11 Jan. 2019 II]
When 100 g of a liquid A at 100°C is added to 50 g of a liquid B at temperature 75°C, the temperature of the mixture becomes 90°C. The temperature of the mixture, if 100 g of liquid A at 100°C is added to 50 g of liquid B at 50°C, will be :
[11 Jan. 2019 II]
Q.207 Correct
Q.207 In-correct
Q.207 Unattempt
A metal ball of mass 0.1 kg is heated upto 500°C and dropped into a vessel of heat capacity 800 JK1 and containing 0.5 kg water. The initial temperature of water and vessel is 30°C. What is the approximate percentage increment in the temperature of the water? [Specific Heat Capacities of water and metal are, respectively, 4200 Jkg1K1 and 400 Jkg1 K1 ]
[11 Jan. 2019 II]
A metal ball of mass 0.1 kg is heated upto 500°C and dropped into a vessel of heat capacity 800 JK1 and containing 0.5 kg water. The initial temperature of water and vessel is 30°C. What is the approximate percentage increment in the temperature of the water? [Specific Heat Capacities of water and metal are, respectively, 4200 Jkg1K1 and 400 Jkg1 K1 ]
[11 Jan. 2019 II]
Q.208 Correct
Q.208 In-correct
Q.208 Unattempt
A heat source at T=103K is connected to another heat reservoir at T=102K by a copper slab which is 1m thick. Given that the thermal conductivity of copper is 0.1WK1m1, the energy flux through it in the steady state is:
[10 Jan. 2019 I]
A heat source at T=103K is connected to another heat reservoir at T=102K by a copper slab which is 1m thick. Given that the thermal conductivity of copper is 0.1WK1m1, the energy flux through it in the steady state is:
[10 Jan. 2019 I]
Q.209 Correct
Q.209 In-correct
Q.209 Unattempt
An unknown metal of mass 192 g heated to a temperature of 100°C was immersed into a brass calorimeter of mass 128 g containing 240 g of water at a temperature of 8.4°C.Calculate the specific heat of the unknown metal if water temperature stablizes at 21.5°C. (Specific heat of brass is 394Jkg1K1)
[10 Jan. 2019 II]
An unknown metal of mass 192 g heated to a temperature of 100°C was immersed into a brass calorimeter of mass 128 g containing 240 g of water at a temperature of 8.4°C.Calculate the specific heat of the unknown metal if water temperature stablizes at 21.5°C. (Specific heat of brass is 394Jkg1K1)
[10 Jan. 2019 II]
Q.210 Correct
Q.210 In-correct
Q.210 Unattempt
Temperature difference of 120°C is maintained between two ends of a uniform rod AB of length 2L. Another bent rod PQ, of same cross-section as AB and length
3L
2
, is connected across AB (See figure). In steady state, temperature difference between P and Q will be close to:

[9 Jan. 2019 I]
Temperature difference of 120°C is maintained between two ends of a uniform rod AB of length 2L. Another bent rod PQ, of same cross-section as AB and length
3L
2
, is connected across AB (See figure). In steady state, temperature difference between P and Q will be close to:

[9 Jan. 2019 I]
Q.211 Correct
Q.211 In-correct
Q.211 Unattempt
A uniform cylindrical rod of length L and radius r, is made from a material whose Young’s modulus of Elasticity equals Y. When this rod is heated by temperature T and simultaneously subjected to a net longitudinal compressional force F, its length remains unchanged. The coefficient of volume expansion, of the material of the rod, is (nearly) equal to :
[12 April 2019 II]
A uniform cylindrical rod of length L and radius r, is made from a material whose Young’s modulus of Elasticity equals Y. When this rod is heated by temperature T and simultaneously subjected to a net longitudinal compressional force F, its length remains unchanged. The coefficient of volume expansion, of the material of the rod, is (nearly) equal to :
[12 April 2019 II]
Q.212 Correct
Q.212 In-correct
Q.212 Unattempt
In an environment, brass and steel wires of length 1m each with areas of cross section 1mm2 are used. The wires are connected in series and one end of the combined wire is connected to a rigid support and other end is subjected to elongation. The stress required to produce a net elongation of 0.2mm is,
[Given, the Young's modulus for steel and brass are, respectively, 120×109Nm2 and 60×109Nm2]
[10 April 2019 II]
In an environment, brass and steel wires of length 1m each with areas of cross section 1mm2 are used. The wires are connected in series and one end of the combined wire is connected to a rigid support and other end is subjected to elongation. The stress required to produce a net elongation of 0.2mm is,
[Given, the Young's modulus for steel and brass are, respectively, 120×109Nm2 and 60×109Nm2]
[10 April 2019 II]
Q.213 Correct
Q.213 In-correct
Q.213 Unattempt
The elastic limit of brass is 379 MPa. What should be the minimum diameter of a brass rod if it is to support a 400 N load without exceeding its elastic limit?
[10 April 2019 II]
The elastic limit of brass is 379 MPa. What should be the minimum diameter of a brass rod if it is to support a 400 N load without exceeding its elastic limit?
[10 April 2019 II]
Q.214 Correct
Q.214 In-correct
Q.214 Unattempt
A steel wire having a radius of 2.0mm, carrying a load of 4kg, is hanging from a ceiling. Given that g=3.1Ams2, what will be the tensile stress that would be developed in the wire?
[9 April 2019 I]
A steel wire having a radius of 2.0mm, carrying a load of 4kg, is hanging from a ceiling. Given that g=3.1Ams2, what will be the tensile stress that would be developed in the wire?
[9 April 2019 I]
Q.215 Correct
Q.215 In-correct
Q.215 Unattempt
A steel wire having a radius of 2.0mm, carrying a load of 4kg, is hanging from a ceiling. Given that g=3.1Ams2, what will be the tensile stress that would be developed in the wire?
[8 April 2019 I]
A steel wire having a radius of 2.0mm, carrying a load of 4kg, is hanging from a ceiling. Given that g=3.1Ams2, what will be the tensile stress that would be developed in the wire?
[8 April 2019 I]
Q.216 Correct
Q.216 In-correct
Q.216 Unattempt
Young’s moduli of two wires A and B are in the ratio 7 : 4.
Wire A is 2 m long and has radius R. Wire B is 1.5 m long and has radius 2 mm. If the two wires stretch by the same length for a given load, then the value of R is close to :
[8 April 2019 II]
Young’s moduli of two wires A and B are in the ratio 7 : 4.
Wire A is 2 m long and has radius R. Wire B is 1.5 m long and has radius 2 mm. If the two wires stretch by the same length for a given load, then the value of R is close to :
[8 April 2019 II]
Q.217 Correct
Q.217 In-correct
Q.217 Unattempt
A boy’s catapult is made of rubber cord which is 42 cm long, with 6 mm diameter of cross-section and of negligible mass. The boy keeps a stone weighing 0.02 kg on it and stretches the cord by 20 cm by applying a constant force.
When released, the stone flies off with a velocity of 20 ms1 . Neglect the change in the area of cross-section of the cord while stretched. The Young’s modulus of rubber is closest to :
[8 April 2019 I]
A boy’s catapult is made of rubber cord which is 42 cm long, with 6 mm diameter of cross-section and of negligible mass. The boy keeps a stone weighing 0.02 kg on it and stretches the cord by 20 cm by applying a constant force.
When released, the stone flies off with a velocity of 20 ms1 . Neglect the change in the area of cross-section of the cord while stretched. The Young’s modulus of rubber is closest to :
[8 April 2019 I]
Q.218 Correct
Q.218 In-correct
Q.218 Unattempt
A cubical block of side 0.5m floats on water with 30% of its volume under water. What is the maximum weight that can be put on the block without fully submerging it under water? [Take, density of water left.=103kgm3]
[10 April 2019(II)]
A cubical block of side 0.5m floats on water with 30% of its volume under water. What is the maximum weight that can be put on the block without fully submerging it under water? [Take, density of water left.=103kgm3]
[10 April 2019(II)]
Q.219 Correct
Q.219 In-correct
Q.219 Unattempt
A submarine experiences a pressure of 5.05×106Pa at depth of d1 in a sea. When it goes further to a depth of d2, it experiences a pressure of 8.08times106Pa. Then d1d1 is approximately (density of water =103kgm3 and acceleration due to gravity =10ms2):
[10 April 2019 (II)]
A submarine experiences a pressure of 5.05×106Pa at depth of d1 in a sea. When it goes further to a depth of d2, it experiences a pressure of 8.08times106Pa. Then d1d1 is approximately (density of water =103kgm3 and acceleration due to gravity =10ms2):
[10 April 2019 (II)]
Q.220 Correct
Q.220 In-correct
Q.220 Unattempt
A wooden block floating in a bucket of water has
4
5
of its volume submerged. When certain amount of an oil poured into the bucket, it is found that the block is just under the oil surface with half of its volume under water and half in oil. The density of oil relative to that of water is:
[9 April 2019 (II)]
A wooden block floating in a bucket of water has
4
5
of its volume submerged. When certain amount of an oil poured into the bucket, it is found that the block is just under the oil surface with half of its volume under water and half in oil. The density of oil relative to that of water is:
[9 April 2019 (II)]
Q.221 Correct
Q.221 In-correct
Q.221 Unattempt
Water from a tap emerges vertically downwards with an initial speed of 1.0ms1. The cross-sectional area of the tap is 104m2. Assume that the pressure is constant throughout the stream of water and that the flow is streamlined. The cross-sectional area of the stream, 0.15m below the tap would be : [Take g=10ms2 )]
[10 April 2019 (II)]
Water from a tap emerges vertically downwards with an initial speed of 1.0ms1. The cross-sectional area of the tap is 104m2. Assume that the pressure is constant throughout the stream of water and that the flow is streamlined. The cross-sectional area of the stream, 0.15m below the tap would be : [Take g=10ms2 )]
[10 April 2019 (II)]
Q.222 Correct
Q.222 In-correct
Q.222 Unattempt
Water from a pipe is coming at a rate of 100 liters per minute. If the radius of the pipe is 5cm, the Reynolds number for the flow is of the order of: ( density of water = 1000kgm3, coefficient of viscosity of water =1mPas)
[8 April 2019 I]
Water from a pipe is coming at a rate of 100 liters per minute. If the radius of the pipe is 5cm, the Reynolds number for the flow is of the order of: ( density of water = 1000kgm3, coefficient of viscosity of water =1mPas)
[8 April 2019 I]
Q.223 Correct
Q.223 In-correct
Q.223 Unattempt
A solid sphere, of radius R acquires a terminal velocity v when falling (due to gravity) through a viscous fluid having a coefficient of viscosity η. The sphere is broken into 27 identical solid spheres. If each of these spheres acquires a terminal velocity, v2, when falling through the same fluid, the ratio (v1v2) equals:
[12 April 2019 (II)]
A solid sphere, of radius R acquires a terminal velocity v when falling (due to gravity) through a viscous fluid having a coefficient of viscosity η. The sphere is broken into 27 identical solid spheres. If each of these spheres acquires a terminal velocity, v2, when falling through the same fluid, the ratio (v1v2) equals:
[12 April 2019 (II)]
Q.224 Correct
Q.224 In-correct
Q.224 Unattempt
The ratio of surface tensions of mercury and water is given to be 7.5 while the ratio of their densities is 13.6 . Their contact angles, with glass, are close to 135° and 0°, respectively. It is observed that mercury gets depressed by an amount h in a capillary tube of radius r1, while water rises by the same amount h in a capillary tube of radius r2. The ratio, (r1r2), is then close to :
[April 2019 (I)]
The ratio of surface tensions of mercury and water is given to be 7.5 while the ratio of their densities is 13.6 . Their contact angles, with glass, are close to 135° and 0°, respectively. It is observed that mercury gets depressed by an amount h in a capillary tube of radius r1, while water rises by the same amount h in a capillary tube of radius r2. The ratio, (r1r2), is then close to :
[April 2019 (I)]
Q.225 Correct
Q.225 In-correct
Q.225 Unattempt
If ' M ' is the mass of water that rises in a capillary tube of radius 'r', then mass of water which will rise in a capillary tube of radius '2r' is:
[9 April 2019 I]
If ' M ' is the mass of water that rises in a capillary tube of radius 'r', then mass of water which will rise in a capillary tube of radius '2r' is:
[9 April 2019 I]
Q.226 Correct
Q.226 In-correct
Q.226 Unattempt
At 40°C, a brass wire of 1 mm radius is hung from the ceiling. A small mass, M is hung from the free end of the wire. When the wire is cooled down from 40°C to 20°C it regains its original length of 0.2 m. The value of M is close to:
(Coefficient of linear expansion and Young's modulus of brass are 105°C and 1011Nm2, respectively ;g=10ms2 )
[12 April 2019 I]
At 40°C, a brass wire of 1 mm radius is hung from the ceiling. A small mass, M is hung from the free end of the wire. When the wire is cooled down from 40°C to 20°C it regains its original length of 0.2 m. The value of M is close to:
(Coefficient of linear expansion and Young's modulus of brass are 105°C and 1011Nm2, respectively ;g=10ms2 )
[12 April 2019 I]
Q.227 Correct
Q.227 In-correct
Q.227 Unattempt
When M1 gram of ice at 10°C (Specific heat =0.5 cal g10C1) is added to M2 gram of water at 50°C, finally no ice is left and the water is at 0°C. The value of latent heat of ice, in cal g1 is:
[12 April 2019 I]
When M1 gram of ice at 10°C (Specific heat =0.5 cal g10C1) is added to M2 gram of water at 50°C, finally no ice is left and the water is at 0°C. The value of latent heat of ice, in cal g1 is:
[12 April 2019 I]
Q.228 Correct
Q.228 In-correct
Q.228 Unattempt
A massless spring (K=800Nm), attached with a mass (500g) is completely immersed in 1kg of water. The spring is stretched by 2cm and released so that it starts vibrating. What would be the order of magnitude of the change in the temperature of water when the vibrations stop completely? (Assume that the water container and spring receive negligible heat and specific heat of mass=400JkgK specific heat of water =4184JkgK)
[9 April 2019 II]
A massless spring (K=800Nm), attached with a mass (500g) is completely immersed in 1kg of water. The spring is stretched by 2cm and released so that it starts vibrating. What would be the order of magnitude of the change in the temperature of water when the vibrations stop completely? (Assume that the water container and spring receive negligible heat and specific heat of mass=400JkgK specific heat of water =4184JkgK)
[9 April 2019 II]
Q.229 Correct
Q.229 In-correct
Q.229 Unattempt
Two materials having coefficients of thermal conductivity 3K ' and ' K ' and thickness ' d ' and ' 3d ', respectively, are joined to form a slab as shown in the figure. The temperatures of the outer surfaces are ' θ2 ' and ' θ1 ' respectively, (θ2>θ1). The temperature at the interface is:

[9 April 2019 II]
Two materials having coefficients of thermal conductivity 3K ' and ' K ' and thickness ' d ' and ' 3d ', respectively, are joined to form a slab as shown in the figure. The temperatures of the outer surfaces are ' θ2 ' and ' θ1 ' respectively, (θ2>θ1). The temperature at the interface is:

[9 April 2019 II]
Q.230 Correct
Q.230 In-correct
Q.230 Unattempt
Two identical beakers A and B contain equal volumes of two different liquids at 60°C each and left to cool down.
Liquid in A has density of 8×102 kg/m3 and specific heat of 2000 J kg1 K1 while liquid in B has density of 103 kg m3and specific heat of 4000 J kg1 K1. Which of the following best describes their temperature versus time graph schematically ? (assume the emissivity of both the beakers to be the same)
[8 April 2019 I]
Two identical beakers A and B contain equal volumes of two different liquids at 60°C each and left to cool down.
Liquid in A has density of 8×102 kg/m3 and specific heat of 2000 J kg1 K1 while liquid in B has density of 103 kg m3and specific heat of 4000 J kg1 K1. Which of the following best describes their temperature versus time graph schematically ? (assume the emissivity of both the beakers to be the same)
[8 April 2019 I]
Q.231 Correct
Q.231 In-correct
Q.231 Unattempt
A body takes 10 minutes to cool from 60°C to 50°C. The temperature of surroundings is constant at 25°C. Then, the temperature of the body after next 10 minutes will be approximately
[Online April 15, 2018]
A body takes 10 minutes to cool from 60°C to 50°C. The temperature of surroundings is constant at 25°C. Then, the temperature of the body after next 10 minutes will be approximately
[Online April 15, 2018]
Q.232 Correct
Q.232 In-correct
Q.232 Unattempt
As shown in the figure, forces of 105N each are applied in opposite directions, on the upper and lower faces of a cube of side 10cm, shifting the upper face parallel to itself by 0.5cm. If the side of another cube of the same material is, 20cm, then under similar conditions as above, the displacement will be:

[Online April 15, 2018]
As shown in the figure, forces of 105N each are applied in opposite directions, on the upper and lower faces of a cube of side 10cm, shifting the upper face parallel to itself by 0.5cm. If the side of another cube of the same material is, 20cm, then under similar conditions as above, the displacement will be:

[Online April 15, 2018]
Q.233 Correct
Q.233 In-correct
Q.233 Unattempt
A solid sphere of radius r made of a soft material of bulk modulus K is surrounded by a liquid in a cylindrical container. A massless piston of area a floats on the surface of the liquid, covering entire cross-section of cylindrical container. When a mass m is placed on the surface of the piston to compress the liquid, the fractional decrement in the radius of the sphere (
dr
r
)
, is:
[2018]
A solid sphere of radius r made of a soft material of bulk modulus K is surrounded by a liquid in a cylindrical container. A massless piston of area a floats on the surface of the liquid, covering entire cross-section of cylindrical container. When a mass m is placed on the surface of the piston to compress the liquid, the fractional decrement in the radius of the sphere (
dr
r
)
, is:
[2018]
Q.234 Correct
Q.234 In-correct
Q.234 Unattempt
A thin uniform tube is bent into a circle of radius r in the vertical plane. Equal volumes of two immiscible liquids, whose densities are ρ1 and ρ1(ρ1>ρ2) fill half the circle. The angle θ between the radius vector passing through the common interface and the vertical is
[Online April 15, 2018]
A thin uniform tube is bent into a circle of radius r in the vertical plane. Equal volumes of two immiscible liquids, whose densities are ρ1 and ρ1(ρ1>ρ2) fill half the circle. The angle θ between the radius vector passing through the common interface and the vertical is
[Online April 15, 2018]
Q.235 Correct
Q.235 In-correct
Q.235 Unattempt
When an air bubble of radius r rises from the bottom to the surface of a lake, its radius becomes
5r
4
. Taking the atmospheric pressure to be equal to 10m height of water column, the depth of the lake would approximately be (ignore the surface tension and the effect of temperature):
[Online April 15, 2018]
When an air bubble of radius r rises from the bottom to the surface of a lake, its radius becomes
5r
4
. Taking the atmospheric pressure to be equal to 10m height of water column, the depth of the lake would approximately be (ignore the surface tension and the effect of temperature):
[Online April 15, 2018]
Q.236 Correct
Q.236 In-correct
Q.236 Unattempt
Two tubes of radii r1 and r2, and lengths l1 and l2, respectively, are connected in series and a liquid flows through each of them in streamline conditions. P1 and P2 are pressure differences across the two tubes. If P2 is 4P1 and l2 is
l1
4
, then the radius r2 will be equal to:
[Online April 9, 2017]
Two tubes of radii r1 and r2, and lengths l1 and l2, respectively, are connected in series and a liquid flows through each of them in streamline conditions. P1 and P2 are pressure differences across the two tubes. If P2 is 4P1 and l2 is
l1
4
, then the radius r2 will be equal to:
[Online April 9, 2017]
Q.237 Correct
Q.237 In-correct
Q.237 Unattempt
An external pressure P is applied on a cube at 0°C so that it is equally compressed from all sides. K is the bulk modulus of the material of the cube and alpha is its coefficient of linear expansion. Suppose we want to bring the cube to its original size by heating. The temperature should be raised by:
[2017]
An external pressure P is applied on a cube at 0°C so that it is equally compressed from all sides. K is the bulk modulus of the material of the cube and alpha is its coefficient of linear expansion. Suppose we want to bring the cube to its original size by heating. The temperature should be raised by:
[2017]
Q.238 Correct
Q.238 In-correct
Q.238 Unattempt
A steel rail of length 5m and area of cross-section 40 cm2 is prevented from expanding along its length while the temperature rises by 10°C. If coefficient of linear expansion and Young's modulus of steel are 1.2×105K1 and 2×1011Nm2 respectively, the force developed in the rail is approximately:
[Online April 9,2017]
A steel rail of length 5m and area of cross-section 40 cm2 is prevented from expanding along its length while the temperature rises by 10°C. If coefficient of linear expansion and Young's modulus of steel are 1.2×105K1 and 2×1011Nm2 respectively, the force developed in the rail is approximately:
[Online April 9,2017]
Q.239 Correct
Q.239 In-correct
Q.239 Unattempt
A compressive force, F is applied at the two ends of a long thin steel rod. It is heated, simultaneously, such that its temperature increases by ΔT. The net change in its length is zero. Let l be the length of the rod, A its area of cross-section, Y its Young's modulus, and α its coefficient of linear expansion. Then, F is equal to :
[Online April 8,2017]
A compressive force, F is applied at the two ends of a long thin steel rod. It is heated, simultaneously, such that its temperature increases by ΔT. The net change in its length is zero. Let l be the length of the rod, A its area of cross-section, Y its Young's modulus, and α its coefficient of linear expansion. Then, F is equal to :
[Online April 8,2017]
Q.240 Correct
Q.240 In-correct
Q.240 Unattempt
A copper ball of mass 100 gm is at a temperature T. It is dropped in a copper calorimeter of mass 100 gm, filled with 170 gm of water at room temperature. Subsequently, the temperature of the system is found to be 75°C. T is given by (Given : room temperature = 30° C, specific heat of copper = 0.1 cal/gm°C
[2017]
A copper ball of mass 100 gm is at a temperature T. It is dropped in a copper calorimeter of mass 100 gm, filled with 170 gm of water at room temperature. Subsequently, the temperature of the system is found to be 75°C. T is given by (Given : room temperature = 30° C, specific heat of copper = 0.1 cal/gm°C
[2017]
Q.241 Correct
Q.241 In-correct
Q.241 Unattempt
In an experiment a sphere of aluminium of mass 0.20 kg is heated upto 150°C. Immediately, it is put into water of volume 150 cc at 27°C kept in a calorimeter of water equivalent to 0.025 kg. Final temperature of the system is 40°C. The specific heat of aluminium is :
(take 4.2 Joule=1 calorie)
[Online April 8, 2017]
In an experiment a sphere of aluminium of mass 0.20 kg is heated upto 150°C. Immediately, it is put into water of volume 150 cc at 27°C kept in a calorimeter of water equivalent to 0.025 kg. Final temperature of the system is 40°C. The specific heat of aluminium is :
(take 4.2 Joule=1 calorie)
[Online April 8, 2017]
Q.242 Correct
Q.242 In-correct
Q.242 Unattempt
A thin 1m long rod has a radius of 5mm. A force of 50πkN is applied at one end to determine its Young's modulus. Assume that the force is exactly known. If the least count in the measurement of all lengths is 0.01mm, which of the following statements is false ?
[Online April 10, 2016]
A thin 1m long rod has a radius of 5mm. A force of 50πkN is applied at one end to determine its Young's modulus. Assume that the force is exactly known. If the least count in the measurement of all lengths is 0.01mm, which of the following statements is false ?
[Online April 10, 2016]
Q.243 Correct
Q.243 In-correct
Q.243 Unattempt
A uniformly tapering conical wire is made from a material of Young's modulus Y and has a normal, unextended length L. The radii, at the upper and lower ends of this conical wire, have values R and 3R, respectively. The upper end of the wire is fixed to a rigid support and a mass M is suspended from its lower end. The equilibrium extended length, of this wire, would equal :
[Online April 9, 2016]
A uniformly tapering conical wire is made from a material of Young's modulus Y and has a normal, unextended length L. The radii, at the upper and lower ends of this conical wire, have values R and 3R, respectively. The upper end of the wire is fixed to a rigid support and a mass M is suspended from its lower end. The equilibrium extended length, of this wire, would equal :
[Online April 9, 2016]
Q.244 Correct
Q.244 In-correct
Q.244 Unattempt
A bottle has an opening of radius a and length b. A cork of length b and radius (a + Δa) where (Δa < < a) is compressed to fit into the opening completely (see figure). If the bulk modulus of cork is B and frictional coefficient between the bottle and cork is m then the force needed to push the cork into the bottle is :

[Online April 10, 2016]
A bottle has an opening of radius a and length b. A cork of length b and radius (a + Δa) where (Δa < < a) is compressed to fit into the opening completely (see figure). If the bulk modulus of cork is B and frictional coefficient between the bottle and cork is m then the force needed to push the cork into the bottle is :

[Online April 10, 2016]
Q.245 Correct
Q.245 In-correct
Q.245 Unattempt
Consider a water jar of radius R that has water filled up to height H and is kept on a stand of height h (see figure). Through a hole of radius r (r < < R) at its bottom, the water leaks out and the stream of water coming down towards the ground has a shape like a funnel as shown in the figure. If the radius of the cross–section of water stream when it hits the ground is x. Then :

[Online April 9, 2016]
Consider a water jar of radius R that has water filled up to height H and is kept on a stand of height h (see figure). Through a hole of radius r (r < < R) at its bottom, the water leaks out and the stream of water coming down towards the ground has a shape like a funnel as shown in the figure. If the radius of the cross–section of water stream when it hits the ground is x. Then :

[Online April 9, 2016]
Q.246 Correct
Q.246 In-correct
Q.246 Unattempt
Which of the following option correctly describes the variation of the speed v and acceleration 'a' of a point mass falling vertically in a viscous medium that applies a force F = –kv, where 'k' is a constant, on the body? (Graphs are schematic and not drawn to scale)
[Online April 9, 2016]
Which of the following option correctly describes the variation of the speed v and acceleration 'a' of a point mass falling vertically in a viscous medium that applies a force F = –kv, where 'k' is a constant, on the body? (Graphs are schematic and not drawn to scale)
[Online April 9, 2016]
Q.247 Correct
Q.247 In-correct
Q.247 Unattempt
If it takes 5 minutes to fill a 15 litre bucket from a water tap of diameter
2
π
cm
then the Reynolds number for the flow is (density of water =103kgm3) and viscosity of water =103 Pa.s) close to:
[Online April 10, 2015]
If it takes 5 minutes to fill a 15 litre bucket from a water tap of diameter
2
π
cm
then the Reynolds number for the flow is (density of water =103kgm3) and viscosity of water =103 Pa.s) close to:
[Online April 10, 2015]
Q.248 Correct
Q.248 In-correct
Q.248 Unattempt
If two glass plates have water between them and are separated by very small distance (see figure), it is very difficult to pull them apart. It is because the water in between forms cylindrical surface on the side that gives rise to lower pressure in the water in comparison to atmosphere. If the radius of the cylindrical surface is R and surface tension of water is T then the pressure in water between the plates is lower by:

[Online April 10, 2015]
If two glass plates have water between them and are separated by very small distance (see figure), it is very difficult to pull them apart. It is because the water in between forms cylindrical surface on the side that gives rise to lower pressure in the water in comparison to atmosphere. If the radius of the cylindrical surface is R and surface tension of water is T then the pressure in water between the plates is lower by:

[Online April 10, 2015]
Q.249 Correct
Q.249 In-correct
Q.249 Unattempt
An experiment takes 10 minutes to raise the temperature of water in a container from 0ºC to 100ºC and another 55 minutes to convert it totally into steam by a heater supplying heat at a uniform rate. Neglecting the specific heat of the container and taking specific heat of water to be 1 cal / g ºC, the heat of vapourization according to this experiment will come out to be :
[Online April 11, 2015]
An experiment takes 10 minutes to raise the temperature of water in a container from 0ºC to 100ºC and another 55 minutes to convert it totally into steam by a heater supplying heat at a uniform rate. Neglecting the specific heat of the container and taking specific heat of water to be 1 cal / g ºC, the heat of vapourization according to this experiment will come out to be :
[Online April 11, 2015]
Q.250 Correct
Q.250 In-correct
Q.250 Unattempt
The pressure that has to be applied to the ends of a steel wire of length 10 cm to keep its length constant when its temperature is raised by 100ºC is:
(For steel Young's modulus is 2×1011Nm2 and coefficient of thermal expansion is 1.1×105K1 )
[2014]
The pressure that has to be applied to the ends of a steel wire of length 10 cm to keep its length constant when its temperature is raised by 100ºC is:
(For steel Young's modulus is 2×1011Nm2 and coefficient of thermal expansion is 1.1×105K1 )
[2014]
Q.251 Correct
Q.251 In-correct
Q.251 Unattempt
Steel ruptures when a shear of 3.5×108Nm2 is applied. The force needed to punch a 1cm diameter hole in a steel sheet 0.3cm thick is nearly:
[Online April 12, 2014]
Steel ruptures when a shear of 3.5×108Nm2 is applied. The force needed to punch a 1cm diameter hole in a steel sheet 0.3cm thick is nearly:
[Online April 12, 2014]
Q.252 Correct
Q.252 In-correct
Q.252 Unattempt
The bulk moduli of ethanol, mercury and water are given as 0.9,25 and 2.2 respectively in units of 109Nm2. For a given value of pressure, the fractional compression in volume is
ΔV
V
. Which of the following statements about
ΔV
V
for these three liquids is correct?
[Online April 11, 2014]
The bulk moduli of ethanol, mercury and water are given as 0.9,25 and 2.2 respectively in units of 109Nm2. For a given value of pressure, the fractional compression in volume is
ΔV
V
. Which of the following statements about
ΔV
V
for these three liquids is correct?
[Online April 11, 2014]
Q.253 Correct
Q.253 In-correct
Q.253 Unattempt
In materials like aluminium and copper, the correct order of magnitude of various elastic modului is:
[Online April 9, 2014]
In materials like aluminium and copper, the correct order of magnitude of various elastic modului is:
[Online April 9, 2014]
Q.254 Correct
Q.254 In-correct
Q.254 Unattempt
There is a circular tube in a vertical plane. Two liquids which do not mix and of densities d1 and d2 are filled in the tube. Each liquid subtends 90° angle at centre. Radius joining their interface makes an angle α with vertical. Ratio
d1
d2
is:

[2014]
There is a circular tube in a vertical plane. Two liquids which do not mix and of densities d1 and d2 are filled in the tube. Each liquid subtends 90° angle at centre. Radius joining their interface makes an angle α with vertical. Ratio
d1
d2
is:

[2014]
Q.255 Correct
Q.255 In-correct
Q.255 Unattempt
An open glass tube is immersed in mercury in such a way that a length of 8 cm extends above the mercury level. The open end of the tube is then closed and sealed and the tube is raised vertically up by additional 46 cm. What will be length of the air column above mercury in the tube now?
(Atmospheric pressure = 76 cm of Hg)
[2014]
An open glass tube is immersed in mercury in such a way that a length of 8 cm extends above the mercury level. The open end of the tube is then closed and sealed and the tube is raised vertically up by additional 46 cm. What will be length of the air column above mercury in the tube now?
(Atmospheric pressure = 76 cm of Hg)
[2014]
Q.256 Correct
Q.256 In-correct
Q.256 Unattempt
In the diagram shown, the difference in the two tubes of the manometer is 5cm, the cross section of the tube at A and B is 6mm2 and 10mm2 respectively. The rate at which water flows through the tube is (g=10ms2)

[Online April 19, 2014]
In the diagram shown, the difference in the two tubes of the manometer is 5cm, the cross section of the tube at A and B is 6mm2 and 10mm2 respectively. The rate at which water flows through the tube is (g=10ms2)

[Online April 19, 2014]
Q.257 Correct
Q.257 In-correct
Q.257 Unattempt
A cylindrical vessel of cross-section A contains water to a height h. There is a hole in the bottom of radius ‘a’. The time in which it will be emptied is:
[Online April 12, 2014]
A cylindrical vessel of cross-section A contains water to a height h. There is a hole in the bottom of radius ‘a’. The time in which it will be emptied is:
[Online April 12, 2014]
Q.258 Correct
Q.258 In-correct
Q.258 Unattempt
Water is flowing at a speed of 1.5ms1 through horizontal tube of cross-sectional area 102m2 and you are trying to stop the flow by your palm. Assuming that the water stops immediately after hitting the palm, the minimum force that you must exert should be
(density of water =103kgm3 )
[Online April 9, 2014]
Water is flowing at a speed of 1.5ms1 through horizontal tube of cross-sectional area 102m2 and you are trying to stop the flow by your palm. Assuming that the water stops immediately after hitting the palm, the minimum force that you must exert should be
(density of water =103kgm3 )
[Online April 9, 2014]
Q.259 Correct
Q.259 In-correct
Q.259 Unattempt
The velocity of water in a river is 18km/ hr near the surface. If the river is 5m deep, find the shearing stress between the horizontal layers of water. The co-efficient of viscosity of water =102 poise.
[Online April 19, 2014]
The velocity of water in a river is 18km/ hr near the surface. If the river is 5m deep, find the shearing stress between the horizontal layers of water. The co-efficient of viscosity of water =102 poise.
[Online April 19, 2014]
Q.260 Correct
Q.260 In-correct
Q.260 Unattempt
The average mass of rain drops is 3.0×105kg and their avarage terminal velocity is 9ms. Calculate the energy transferred by rain to each square metre of the surface at a place which receives 100cm of rain in a year.
[Online April 11, 2014]
The average mass of rain drops is 3.0×105kg and their avarage terminal velocity is 9ms. Calculate the energy transferred by rain to each square metre of the surface at a place which receives 100cm of rain in a year.
[Online April 11, 2014]
Q.261 Correct
Q.261 In-correct
Q.261 Unattempt
A tank with a small hole at the bottom has been filled with water and kerosene (specific gravity 0.8 ). The height of water is 3m and that of kerosene 2m. When the hole is opened the velocity of fluid coming out from it is nearly:
(take g=10ms2 and density of water =103kgm3 )
[Online April 11, 2014]
A tank with a small hole at the bottom has been filled with water and kerosene (specific gravity 0.8 ). The height of water is 3m and that of kerosene 2m. When the hole is opened the velocity of fluid coming out from it is nearly:
(take g=10ms2 and density of water =103kgm3 )
[Online April 11, 2014]
Q.262 Correct
Q.262 In-correct
Q.262 Unattempt
On heating water, bubbles being formed at the bottom of the vessel detach and rise. Take the bubbles to be spheres of radius R and making a circular contact of radius r with the bottom of the vessel. If r<<R and the surface tension of water is T, value of r just before bubbles detach is: (density of water is ρw )

[2014]
On heating water, bubbles being formed at the bottom of the vessel detach and rise. Take the bubbles to be spheres of radius R and making a circular contact of radius r with the bottom of the vessel. If r<<R and the surface tension of water is T, value of r just before bubbles detach is: (density of water is ρw )

[2014]
Q.263 Correct
Q.263 In-correct
Q.263 Unattempt
Two soap bubbles coalesce to form a single bubble. If V is the subsequent change in volume of contained air and S change in total surface area, T is the surface tension and P atmospheric pressure, then which of the following relation is correct?
[Online April 12, 2014]
Two soap bubbles coalesce to form a single bubble. If V is the subsequent change in volume of contained air and S change in total surface area, T is the surface tension and P atmospheric pressure, then which of the following relation is correct?
[Online April 12, 2014]
Q.264 Correct
Q.264 In-correct
Q.264 Unattempt
An air bubble of radius 0.1cm is in a liquid having surface tension 0.06Nm and density 103kgm3. The pressure inside the bubble is 1100Nm2 greater than the atmospheric pressure. At what depth is the bubble below the surface of the liquid? (g=9.8ms2)
[Online April 11, 2014]
An air bubble of radius 0.1cm is in a liquid having surface tension 0.06Nm and density 103kgm3. The pressure inside the bubble is 1100Nm2 greater than the atmospheric pressure. At what depth is the bubble below the surface of the liquid? (g=9.8ms2)
[Online April 11, 2014]
Q.265 Correct
Q.265 In-correct
Q.265 Unattempt
A capillary tube is immersed vertically in water and the height of the water column is x. When this arrangement is taken into a mine of depth d, the height of the water column is y. If R is the radius of earth, the ratio
x
y
is:
[Online April 9, 2014]
A capillary tube is immersed vertically in water and the height of the water column is x. When this arrangement is taken into a mine of depth d, the height of the water column is y. If R is the radius of earth, the ratio
x
y
is:
[Online April 9, 2014]
Q.266 Correct
Q.266 In-correct
Q.266 Unattempt
Three rods of Copper, Brass and Steel are welded together to form a Y shaped structure. Area of cross - section of each rod = 4 cm2 . End of copper rod is maintained at 100ºC where as ends of brass and steel are kept at 0ºC. Lengths of the copper, brass and steel rods are 46, 13 and 12 cms respectively. The rods are thermally insulated from surroundings excepts at ends. Thermal conductivities of copper, brass and steel are 0.92, 0.26 and 0.12 CGS units respectively. Rate of heat flow through copper rod is:
[2014]
Three rods of Copper, Brass and Steel are welded together to form a Y shaped structure. Area of cross - section of each rod = 4 cm2 . End of copper rod is maintained at 100ºC where as ends of brass and steel are kept at 0ºC. Lengths of the copper, brass and steel rods are 46, 13 and 12 cms respectively. The rods are thermally insulated from surroundings excepts at ends. Thermal conductivities of copper, brass and steel are 0.92, 0.26 and 0.12 CGS units respectively. Rate of heat flow through copper rod is:
[2014]
Q.267 Correct
Q.267 In-correct
Q.267 Unattempt
A black coloured solid sphere of radius R and mass M is inside a cavity with vacuum inside. The walls of the cavity are maintained at temperature T0. The initial temperature of the sphere is 3T0. If the specific heat of the material of the sphere varies as αT3 per unit mass with the temperature T of the sphere, where α is a constant, then the time taken for the sphere to cool down to temperature 2T0 will be (σ is Stefan Boltzmann constant)
[Online April 19,2014]
A black coloured solid sphere of radius R and mass M is inside a cavity with vacuum inside. The walls of the cavity are maintained at temperature T0. The initial temperature of the sphere is 3T0. If the specific heat of the material of the sphere varies as αT3 per unit mass with the temperature T of the sphere, where α is a constant, then the time taken for the sphere to cool down to temperature 2T0 will be (σ is Stefan Boltzmann constant)
[Online April 19,2014]
Q.268 Correct
Q.268 In-correct
Q.268 Unattempt
Water of volume 2 L in a closed container is heated with a coil of 1 kW. While water is heated, the container loses energy at a rate of 160 J/s. In how much time will the temperature of water rise from 27°C to 77°C? (Specific heat of water is 4.2 kJ/kg and that of the container is negligible).
[Online April 9, 2014]
Water of volume 2 L in a closed container is heated with a coil of 1 kW. While water is heated, the container loses energy at a rate of 160 J/s. In how much time will the temperature of water rise from 27°C to 77°C? (Specific heat of water is 4.2 kJ/kg and that of the container is negligible).
[Online April 9, 2014]
Q.269 Correct
Q.269 In-correct
Q.269 Unattempt
Hot water cools from 60°C to 50°C in the first 10 minutes and to 42°C in the next 10 minutes. The temperature of the surroundings is:
[Online April 12, 2014]
Hot water cools from 60°C to 50°C in the first 10 minutes and to 42°C in the next 10 minutes. The temperature of the surroundings is:
[Online April 12, 2014]
Q.270 Correct
Q.270 In-correct
Q.270 Unattempt
A hot body, obeying Newton’s law of cooling is cooling down from its peak value 80°C to an ambient temperature of 30°C. It takes 5 minutes in cooling down from 80°C to 40°C. How much time will it take to cool down from 62°C to 32°C?
(Given In 2 = 0.693, In 5 = 1.609)
[Online April 11, 2014]
A hot body, obeying Newton’s law of cooling is cooling down from its peak value 80°C to an ambient temperature of 30°C. It takes 5 minutes in cooling down from 80°C to 40°C. How much time will it take to cool down from 62°C to 32°C?
(Given In 2 = 0.693, In 5 = 1.609)
[Online April 11, 2014]
Q.271 Correct
Q.271 In-correct
Q.271 Unattempt
Two blocks of masses m and M are connected by means of a metal wire of cross-sectional area A passing over a frictionless fixed pulley as shown in the figure. The system is then released. If M = 2 m, then the stress produced in the wire is :

[Online April 25, 2013]
Two blocks of masses m and M are connected by means of a metal wire of cross-sectional area A passing over a frictionless fixed pulley as shown in the figure. The system is then released. If M = 2 m, then the stress produced in the wire is :

[Online April 25, 2013]
Q.272 Correct
Q.272 In-correct
Q.272 Unattempt
A copper wire of length 1.0m and a steel wire of length 0.5m having equal cross-sectional areas are joined end to end. The composite wire is stretched by a certain load which stretches the copper wire by 1mm. If the Young's modulii of copper and steel are respectively 1.0×1011Nm2 and 2.0×1011Nm2, the total extension of the composite wire is :
[Online April 23, 2013]
A copper wire of length 1.0m and a steel wire of length 0.5m having equal cross-sectional areas are joined end to end. The composite wire is stretched by a certain load which stretches the copper wire by 1mm. If the Young's modulii of copper and steel are respectively 1.0×1011Nm2 and 2.0×1011Nm2, the total extension of the composite wire is :
[Online April 23, 2013]
Q.273 Correct
Q.273 In-correct
Q.273 Unattempt
A uniform wire (Young's modulus 2×1011Nm2 ) is subjected to longitudinal tensile stress of 5×107Nm2. If the overall volume change in the wire is 0.02%, the fractional decrease in the radius of the wire is close to :
[Online April 22, 2013]
A uniform wire (Young's modulus 2×1011Nm2 ) is subjected to longitudinal tensile stress of 5×107Nm2. If the overall volume change in the wire is 0.02%, the fractional decrease in the radius of the wire is close to :
[Online April 22, 2013]
Q.274 Correct
Q.274 In-correct
Q.274 Unattempt
If the ratio of lengths, radii and Young's moduli of steel and brass wires in the figure are a, b and c respectively, then the corresponding ratio of increase in their lengths is :

[Online April 9, 2013]
If the ratio of lengths, radii and Young's moduli of steel and brass wires in the figure are a, b and c respectively, then the corresponding ratio of increase in their lengths is :

[Online April 9, 2013]
Q.275 Correct
Q.275 In-correct
Q.275 Unattempt
A uniform cylinder of length L and mass M having cross sectional area A is suspended, with its length vertical, from a fixed point by a massless spring such that it is half submerged in a liquid of density sigma at equilibrium position. The extension x0 of the spring when it is in equilibrium is:
[2013]
A uniform cylinder of length L and mass M having crosssectional area A is suspended, with its length vertical, from a fixed point by a massless spring such that it is half submerged in a liquid of density sigma at equilibrium position. The extension x0 of the spring when it is in equilibrium is:
[2013]
Q.276 Correct
Q.276 In-correct
Q.276 Unattempt
Air of density 1.2kgm3 is blowing across the horizontal wings of an aeroplane in such a way that its speeds above and below the wings are 150ms1 and 100ms1, respectively. The pressure difference between the upper and lower sides of the wings, is:
[Online April 22, 2013]
Air of density 1.2kgm3 is blowing across the horizontal wings of an aeroplane in such a way that its speeds above and below the wings are 150ms1 and 100ms1, respectively. The pressure difference between the upper and lower sides of the wings, is:
[Online April 22, 2013]
Q.277 Correct
Q.277 In-correct
Q.277 Unattempt
In an experiment, a small steel ball falls through a liquid at a constant speed of 10 cm/s. If the steel ball is pulled upward with a force equal to twice its effective weight, how fast will it move upward ?
[Online April 25, 2013]
In an experiment, a small steel ball falls through a liquid at a constant speed of 10 cm/s. If the steel ball is pulled upward with a force equal to twice its effective weight, how fast will it move upward ?
[Online April 25, 2013]
Q.278 Correct
Q.278 In-correct
Q.278 Unattempt
Wax is coated on the inner wall of a capillary tube and the tube is then dipped in water. Then, compared to the unwaxed capillary, the angle of contact θ and the height h upto which water rises change. These changes are :
[Online April 23, 2013]
Wax is coated on the inner wall of a capillary tube and the tube is then dipped in water. Then, compared to the unwaxed capillary, the angle of contact θ and the height h upto which water rises change. These changes are :
[Online April 23, 2013]
Q.279 Correct
Q.279 In-correct
Q.279 Unattempt
A thin tube sealed at both ends is 100cm long. It lies horizontally, the middle 20cm containing mercury and two equal ends containing air at standard atmospheric pressure. If the tube is now turned to a vertical position, by what amount will the mercury be displaced?

(Given : cross-section of the tube can be assumed to be uniform)
[Online April 23, 2013]
A thin tube sealed at both ends is 100cm long. It lies horizontally, the middle 20cm containing mercury and two equal ends containing air at standard atmospheric pressure. If the tube is now turned to a vertical position, by what amount will the mercury be displaced?

(Given : cross-section of the tube can be assumed to be uniform)
[Online April 23, 2013]
Q.280 Correct
Q.280 In-correct
Q.280 Unattempt
This question has Statement- 1 and Statement-2. Of the four choices given after the Statements, choose the one that best describes the two Statements.
Statement-1: A capillary is dipped in a liquid and liquid rises to a height h in it. As the temperature of the liquid is raised, the height h increases (if the density of the liquid and the angle of contact remain the same).
Statement-2: Surface tension of a liquid decreases with the rise in its temperature.
[Online April 9, 2013]
This question has Statement- 1 and Statement-2. Of the four choices given after the Statements, choose the one that best describes the two Statements.
Statement-1: A capillary is dipped in a liquid and liquid rises to a height h in it. As the temperature of the liquid is raised, the height h increases (if the density of the liquid and the angle of contact remain the same).
Statement-2: Surface tension of a liquid decreases with the rise in its temperature.
[Online April 9, 2013]
Q.281 Correct
Q.281 In-correct
Q.281 Unattempt
The ratio of the coefficient of volume expansion of a glass container to that of a viscous liquid kept inside the container is 1 : 4. What fraction of the inner volume of the container should the liquid occupy so that the volume of the remaining vacant space will be same at all temperatures ?
[Online April 23, 2013]
The ratio of the coefficient of volume expansion of a glass container to that of a viscous liquid kept inside the container is 1 : 4. What fraction of the inner volume of the container should the liquid occupy so that the volume of the remaining vacant space will be same at all temperatures ?
[Online April 23, 2013]
Q.282 Correct
Q.282 In-correct
Q.282 Unattempt
On a linear temperature scale Y, water freezes at – 160° Y and boils at – 50° Y. On this Y scale, a temperature of 340 K would be read as : (water freezes at 273 K and boils at 373 K)
[Online April 9, 2013]
On a linear temperature scale Y, water freezes at – 160° Y and boils at – 50° Y. On this Y scale, a temperature of 340 K would be read as : (water freezes at 273 K and boils at 373 K)
[Online April 9, 2013]
Q.283 Correct
Q.283 In-correct
Q.283 Unattempt
Assume that a drop of liquid evaporates by decrease in its surface energy, so that its temperature remains unchanged. What should be the minimum radius of the drop for this to be possible? The surface tension is T, density of liquid is ρ and L is its latent heat of vaporization.
[2013]
Assume that a drop of liquid evaporates by decrease in its surface energy, so that its temperature remains unchanged. What should be the minimum radius of the drop for this to be possible? The surface tension is T, density of liquid is ρ and L is its latent heat of vaporization.
[2013]
Q.284 Correct
Q.284 In-correct
Q.284 Unattempt
A mass of 50g of water in a closed vessel, with surroundings at a constant temperature takes 2 minutes to cool from 30°C to 25°C. A mass of 100g of another liquid in an identical vessel with identical surroundings takes the same time to cool from 30° C to 25° C. The specific heat of the liquid is :
(The water equivalent of the vessel is 30g.)
[Online April 25, 2013]
A mass of 50g of water in a closed vessel, with surroundings at a constant temperature takes 2 minutes to cool from 30°C to 25°C. A mass of 100g of another liquid in an identical vessel with identical surroundings takes the same time to cool from 30° C to 25° C. The specific heat of the liquid is :
(The water equivalent of the vessel is 30g.)
[Online April 25, 2013]
Q.285 Correct
Q.285 In-correct
Q.285 Unattempt
500 g of water and 100 g of ice at 0°C are in a calorimeter whose water equivalent is 40 g. 10 g of steam at 100°C is added to it. Then water in the calorimeter is : (Latent heat of ice = 80 cal/g, Latent heat of steam = 540 cal/ g)
[Online April 23, 2013]
500 g of water and 100 g of ice at 0°C are in a calorimeter whose water equivalent is 40 g. 10 g of steam at 100°C is added to it. Then water in the calorimeter is : (Latent heat of ice = 80 cal/g, Latent heat of steam = 540 cal/ g)
[Online April 23, 2013]
Q.286 Correct
Q.286 In-correct
Q.286 Unattempt
Given that 1 g of water in liquid phase has volume 1 cm3and in vapour phase 1671 cm3 at atmospheric pressure and the latent heat of vaporization of water is 2256 J/g; the change in the internal energy in joules for 1 g of water at 373 K when it changes from liquid phase to vapour phase at the same temperature is :
[Online April 22, 2013]
Given that 1 g of water in liquid phase has volume 1 cm3and in vapour phase 1671 cm3 at atmospheric pressure and the latent heat of vaporization of water is 2256 J/g; the change in the internal energy in joules for 1 g of water at 373 K when it changes from liquid phase to vapour phase at the same temperature is :
[Online April 22, 2013]
Q.287 Correct
Q.287 In-correct
Q.287 Unattempt
If a piece of metal is heated to temperature θ and then allowed to cool in a room which is at temperature θ0 , the graph between the temperature T of the metal and time twill be closest to
[2013]
If a piece of metal is heated to temperature θ and thenallowed to cool in a room which is at temperature θ0 , the graph between the temperature T of the metal and time twill be closest to
[2013]
Q.288 Correct
Q.288 In-correct
Q.288 Unattempt
A steel wire can sustain 100 kg weight without breaking. If the wire is cut into two equal parts, each part can sustain a weight of
[Online May 19, 2012]
A steel wire can sustain 100 kg weight without breaking. If the wire is cut into two equal parts, each part can sustain a weight of
[Online May 19, 2012]
Q.289 Correct
Q.289 In-correct
Q.289 Unattempt
A structural steel rod has a radius of 10 mm and length of 1.0 m. A 100 kN force stretches it along its length. Young’s modulus of structural steel is 2×1011Nm2. The percentage strain is about
[Online May 7, 2012]
A structural steel rod has a radius of 10 mm and length of 1.0 m. A 100 kN force stretches it along its length. Young’s modulus of structural steel is 2×1011Nm2. The percentage strain is about
[Online May 7, 2012]
Q.290 Correct
Q.290 In-correct
Q.290 Unattempt
The load versus elongation graphs for four wires of same length and made of the same material are shown in the figure. The thinnest wire is represented by the line

[Online May 7, 2012]
The load versus elongation graphs for four wires of same length and made of the same material are shown in the figure. The thinnest wire is represented by the line

[Online May 7, 2012]
Q.291 Correct
Q.291 In-correct
Q.291 Unattempt
In a cylindrical water tank, there are two small holes A and B on the wall at a depth of h1, from the surface of water and at a height of h2 from the bottom of water tank. Surface of water is at heigh H from the bottom of water tank. Water coming out from both holes strikes the ground at the same point S. Find the ratio of h1 and h2

[Online May 26, 2012]
In a cylindrical water tank, there are two small holes A and B on the wall at a depth of h1, from the surface of water and at a height of h2 from the bottom of water tank. Surface of water is at heigh H from the bottom of water tank. Water coming out from both holes strikes the ground at the same point S. Find the ratio of h1 and h2

[Online May 26, 2012]
Q.292 Correct
Q.292 In-correct
Q.292 Unattempt
Water is flowing through a horizontal tube having cross sectional areas of its two ends being A and A such that the ratio AA is 5 . If the pressure difference of water between the two ends is 3×105Nm2, the velocity of water with which it enters the tube will be (neglect gravity effects)
[Online May 12, 2012 ]
Water is flowing through a horizontal tube having cross sectional areas of its two ends being A and A such that the ratio AA is 5 . If the pressure difference of water between the two ends is 3×105Nm2, the velocity of water with which it enters the tube will be (neglect gravity effects)
[Online May 12, 2012 ]
Q.293 Correct
Q.293 In-correct
Q.293 Unattempt
A square hole of side length l is made at a depth of h and a circular hole of radius r is made at a depth of 4h from the surface of water in a water tank kept on a horizontal surface.
If l < < h, r < < h and the rate of water flow from the holes is the same, then r is equal to

[May 7, 2012]
A square hole of side length l is made at a depth of h and a circular hole of radius r is made at a depth of 4h from the surface of water in a water tank kept on a horizontal surface.
If l < < h, r < < h and the rate of water flow from the holes is the same, then r is equal to

[May 7, 2012]
Q.294 Correct
Q.294 In-correct
Q.294 Unattempt
The terminal velocity of a small sphere of radius a in a viscous liquid is proportional to
[Online May 26, 2012]
The terminal velocity of a small sphere of radius a in a viscous liquid is proportional to
[Online May 26, 2012]
Q.295 Correct
Q.295 In-correct
Q.295 Unattempt
A large number of liquid drops each of radius r coalesce to from a single drop of radius R. The energy released in the process is converted into kinetic energy of the big drop so formed. The speed of the big drop is (given, surface tension of liquid T, density ρ )
[Online April 19, 2014, 2012]
A large number of liquid drops each of radius r coalesce to from a single drop of radius R. The energy released in the process is converted into kinetic energy of the big drop so formed. The speed of the big drop is (given, surface tension of liquid T, density ρ )
[Online April 19, 2014, 2012]
Q.296 Correct
Q.296 In-correct
Q.296 Unattempt
A thin liquid film formed between a U-shaped wire and a light slider supports a weight of 1.5×102N (see figure). The length of the slider is 30cm and its weight is negligible. The surface tension of the liquid film is

[2012]
A thin liquid film formed between a U-shaped wire and a light slider supports a weight of 1.5×102N (see figure). The length of the slider is 30cm and its weight is negligible. The surface tension of the liquid film is

[2012]
Q.297 Correct
Q.297 In-correct
Q.297 Unattempt
A wooden wheel of radius R is made of two semicircular part (see figure). The two parts are held together by a ring made of a metal strip of cross sectional area S and length L. L is slightly less than 2πR. To fit the ring on the wheel, it is heated so that its temperature rises by ΔT and it just steps over the wheel. As it cools down to surrounding temperature, it presses the semicircular parts together. If the coefficient of linear expansion of the metal is α, and its Young's modulus is Y, the force that one part of the wheel applies on the other part is:

[2012]
A wooden wheel of radius R is made of two semicircular part (see figure). The two parts are held together by a ring made of a metal strip of cross sectional area S and length L. L is slightly less than 2πR. To fit the ring on the wheel, it is heated so that its temperature rises by ΔT and it just steps over the wheel. As it cools down to surrounding temperature, it presses the semicircular parts together. If the coefficient of linear expansion of the metal is α, and its Young's modulus is Y, the force that one part of the wheel applies on the other part is:

[2012]
Q.298 Correct
Q.298 In-correct
Q.298 Unattempt
A large cylindrical rod of length L is made by joining two identical rods of copper and steel of length (
l
2
)
each.
The rods are completely insulated from the surroundings. If the free end of copper rod is maintained at 100°C and that of steel at 0°C then the temperature of junction is (Thermal conductivity of copper is 9 times that of steel)
[Online May 19, 2012]
A large cylindrical rod of length L is made by joining two identical rods of copper and steel of length (
l
2
)
each.
The rods are completely insulated from the surroundings. If the free end of copper rod is maintained at 100°C and that of steel at 0°C then the temperature of junction is (Thermal conductivity of copper is 9 times that of steel)
[Online May 19, 2012]
Q.299 Correct
Q.299 In-correct
Q.299 Unattempt
The heat radiated per unit area in 1 hour by a furnace whose temperature is 3000 K is (s=5.7×108Wm2K4)
[Online May 7, 2012]
The heat radiated per unit area in 1 hour by a furnace whose temperature is 3000 K is (s=5.7×108Wm2K4)
[Online May 7, 2012]
Q.300 Correct
Q.300 In-correct
Q.300 Unattempt
A liquid in a beaker has temperature θ(t) at time t and θ0 is temperature of surroundings, then according to Newton's law of cooling the correct graph between loge(θθ0) and t is :
[2012]
A liquid in a beaker has temperature θ(t) at time t and θ0 is temperature of surroundings, then according to Newton's law of cooling the correct graph between loge(θθ0) and t is :
[2012]
Q.301 Correct
Q.301 In-correct
Q.301 Unattempt
Water is flowing continuously from a tap having an internal diameter 8×103m. The water velocity as it leaves the tap is 0.4ms1. The diameter of the water stream at a distance 2 ×101m below the tap is close to:
[2011]
Water is flowing continuously from a tap having an internal diameter 8×103m. The water velocity as it leaves the tap is 0.4ms1. The diameter of the water stream at a distance 2 ×101m below the tap is close to:
[2011]
Q.302 Correct
Q.302 In-correct
Q.302 Unattempt
If a ball of steel (density ρ=7.8gcm3) attains a terminal velocity of 10cms1 when falling in water (Coefficient of viscosity ηwater =8.5×104Pa.s ), then, its terminal velocity in glycerine (ρ=1.2gcm3,η=13.2Pa.s) would be, nearly
[2011 RS]
If a ball of steel (density ρ=7.8gcm3) attains a terminal velocity of 10cms1 when falling in water (Coefficient of viscosity ηwater =8.5×104Pa.s ), then, its terminal velocity in glycerine (ρ=1.2gcm3,η=13.2Pa.s) would be, nearly
[2011 RS]
Q.303 Correct
Q.303 In-correct
Q.303 Unattempt
Work done in increasing the size of a soap bubble from a radius of 3cm to 5cm is nearly (Surface tension of soap solution =0.03Nm1)
[2011]
Work done in increasing the size of a soap bubble from a radius of 3cm to 5cm is nearly (Surface tension of soap solution =0.03Nm1)
[2011]
Q.304 Correct
Q.304 In-correct
Q.304 Unattempt
Two mercury drops (each of radius ' r ') merge to form bigger drop. The surface energy of the bigger drop, if T is the surface tension, is :
[2011 RS]
Two mercury drops (each of radius ' r ') merge to form bigger drop. The surface energy of the bigger drop, if T is the surface tension, is :
[2011 RS]
Q.305 Correct
Q.305 In-correct
Q.305 Unattempt
100g of water is heated from 30°C to 50°C. Ignoring the slight expansion of the water, the change in its internal energy is (specific heat of water is 4184 J/kg/K):
[2011]
100g of water is heated from 30°C to 50°C. Ignoring the slight expansion of the water, the change in its internal energy is (specific heat of water is 4184 J/kg/K):
[2011]
Q.306 Correct
Q.306 In-correct
Q.306 Unattempt
The specific heat capacity of a metal at low temperature(T) is given as
Cp(kJK1kg1)=32(
T
400
)
3

A 100 gram vessel of this metal is to be cooled from 20ºK to 4ºK by a special refrigerator operating at room temperature (27°C). The amount of work required to cool the vessel is
[2011 RS]
The specific heat capacity of a metal at low temperature(T) is given as
Cp(kJK1kg1)=32(
T
400
)
3

A 100 gram vessel of this metal is to be cooled from 20ºK to 4ºK by a special refrigerator operating at room temperature (27°C). The amount of work required to cool the vessel is
[2011 RS]
Q.307 Correct
Q.307 In-correct
Q.307 Unattempt
A ball is made of a material of density rho where ρoil<ρ<ρwater with ρoil and ρwater represe-nting the densities of oil and water, respectively. The oil and water are immiscible. If the above ball is in equilibrium in a mixture of this oil and water, which of the following pictures represents its equilibrium position?
[2010]
A ball is made of a material of density rho where ρoil<ρ<ρwater with ρoil and ρwater represe-nting the densities of oil and water, respectively. The oil and water are immiscible. If the above ball is in equilibrium in a mixture of this oil and water, which of the following pictures represents its equilibrium position?
[2010]
Q.308 Correct
Q.308 In-correct
Q.308 Unattempt
Two identical charged spheres are suspended by strings of equal lengths. The strings make an angle of 30° with each other. When suspended in a liquid of density 0.8gcm3, the angle remains the same. If density of the material of the sphere is 1.6gcm3, the dielectric constant of the liquid is
[2010]
Two identical charged spheres are suspended by strings of equal lengths. The strings make an angle of 30° with each other. When suspended in a liquid of density 0.8gcm3, the angle remains the same. If density of the material of the sphere is 1.6gcm3, the dielectric constant of the liquid is
[2010]
Q.309 Correct
Q.309 In-correct
Q.309 Unattempt
Two wires are made of the same material and have the same volume. However wire 1 has cross-sectional area A and wire 2 has cross-sectional area 3A. If the length of wire 1 increases by Δx on applying force F, how much force is needed to stretch wire 2 by the same amount?
[2009]
Two wires are made of the same material and have the same volume. However wire 1 has cross-sectional area A and wire 2 has cross-sectional area 3A. If the length of wire 1 increases by Δx on applying force F, how much force is needed to stretch wire 2 by the same amount?
[2009]
Q.310 Correct
Q.310 In-correct
Q.310 Unattempt
A long metallic bar is carrying heat from one of its ends to the other end under steady–state. The variation of temperature θ along the length x of the bar from its hot end is best described by which of the following figures?
[2009]
A long metallic bar is carrying heat from one of its ends to the other end under steady–state. The variation of temperature θ along the length x of the bar from its hot end is best described by which of the following figures?
[2009]
Q.311 Correct
Q.311 In-correct
Q.311 Unattempt
A jar is filled with two non-mixing liquids 1 and 2 having densities ρ1 and, ρ2 respectively. A solid ball, made of a material of density rho3, is dropped in the jar. It comes to equilibrium in the position shown in the figure. Which of the following is true for ρ1,ρ2 and ρ3 ?
[2008]
A jar is filled with two non-mixing liquids 1 and 2 having densities ρ1 and, ρ2 respectively. A solid ball, made of a material of density rho3, is dropped in the jar. It comes to equilibrium in the position shown in the figure. Which of the following is true for ρ1,ρ2 and ρ3 ?
[2008]
Q.312 Correct
Q.312 In-correct
Q.312 Unattempt
A spherical solid ball of volume V is made of a material of density ρ1. It is falling through a liquid of density ρ1(ρ2<ρ1). Assume that the liquid applies a viscous force on the ball that is proportional to the square of its speed v, i.e., Fviscous=kv2(k>0). The terminal speed of the ball is
[2008]
A spherical solid ball of volume V is made of a material of density ρ1. It is falling through a liquid of density ρ1(ρ2<ρ1). Assume that the liquid applies a viscous force on the ball that is proportional to the square of its speed v, i.e., Fviscous=kv2(k>0). The terminal speed of the ball is
[2008]
Q.313 Correct
Q.313 In-correct
Q.313 Unattempt
A capillary tube (A) is dipped in water. Another identical tube (B) is dipped in a soap-water solution. Which of the following shows the relative nature of the liquid columns in the two tubes?
[2008]
A capillary tube (A) is dipped in water. Another identical tube (B) is dipped in a soap-water solution. Which of the following shows the relative nature of the liquid columns in the two tubes?
[2008]
Q.314 Correct
Q.314 In-correct
Q.314 Unattempt
One end of a thermally insulated rod is kept at a temperature T1 and the other at T2. The rod is composed of two sections of length l1 and l2 and thermal conductivities K1 and K2 respectively. The temperature at the interface of the two section is

[2007]
One end of a thermally insulated rod is kept at a temperature T1 and the other at T2. The rod is composed of two sections of length l1 and l2 and thermal conductivities K1 and K2 respectively. The temperature at the interface of the two section is

[2007]
Q.315 Correct
Q.315 In-correct
Q.315 Unattempt
A wire elongates by l mm when a load W is hanged from it. If the wire goes over a pulley and two weights W each are hung at the two ends, the elongation of the wire will be (in mm)
[2006]
A wire elongates by l mm when a load W is hanged from it. If the wire goes over a pulley and two weights W each are hung at the two ends, the elongation of the wire will be (in mm)
[2006]
Q.316 Correct
Q.316 In-correct
Q.316 Unattempt
If the terminal speed of a sphere of gold (density =19.5kgm3 ) is 0.2ms in a viscous liquid (density =1.5 kgm3), find the terminal speed of a sphere of silver (density =10.5kgm3 ) of the same size in the same liquid
[2006]
If the terminal speed of a sphere of gold (density =19.5kgm3 ) is 0.2ms in a viscous liquid (density =1.5 kgm3), find the terminal speed of a sphere of silver (density =10.5kgm3 ) of the same size in the same liquid
[2006]
Q.317 Correct
Q.317 In-correct
Q.317 Unattempt
Assuming the Sun to be a spherical body of radius R at a temperature of TK, evaluate the total radiant powered incident of Earth at a distance r from the Sun
[2006]
Assuming the Sun to be a spherical body of radius R at a temperature of TK, evaluate the total radiant powered incident of Earth at a distance r from the Sun
[2006]
Q.318 Correct
Q.318 In-correct
Q.318 Unattempt
Two rigid boxes containing different ideal gases are placed on a table. Box A contains one mole of nitrogen at temperature T0, while Box contains one mole of helium at temperature (
7
3
)
T0
. The boxes are then put into thermal contact with each other, and heat flows between them until the gases reach a common final temperature (ignore the heat capacity of boxes). Then, the final temperature of the gases, Tf in terms of T0 is
[2006]
Two rigid boxes containing different ideal gases are placed on a table. Box A contains one mole of nitrogen at temperature T0, while Box contains one mole of helium at temperature (
7
3
)
T0
. The boxes are then put into thermal contact with each other, and heat flows between them until the gases reach a common final temperature (ignore the heat capacity of boxes). Then, the final temperature of the gases, Tf in terms of T0 is
[2006]
Q.319 Correct
Q.319 In-correct
Q.319 Unattempt
If ‘S’ is stress and ‘Y’ is young’s modulus of material of a wire, the energy stored in the wire per unit volume is
[2005]
If ‘S’ is stress and ‘Y’ is young’s modulus of material of a wire, the energy stored in the wire per unit volume is
[2005]
Q.320 Correct
Q.320 In-correct
Q.320 Unattempt
A 20cm long capillary tube is dipped in water. The water rises up to 8cm. If the entire arrangement is put in a freely falling elevator the length of water column in the capillary tube will be
[2005]
A 20cm long capillary tube is dipped in water. The water rises up to 8cm. If the entire arrangement is put in a freely falling elevator the length of water column in the capillary tube will be
[2005]
Q.321 Correct
Q.321 In-correct
Q.321 Unattempt
The figure shows a system of two concentric spheres of radii r1 and r2 are kept at temperatures T1 and T2, respectively. The radial rate of flow of heat in a substance between the two concentric spheres is proportional to

[2005]
The figure shows a system of two concentric spheres of radii r1 and r2 are kept at temperatures T1 and T2, respectively. The radial rate of flow of heat in a substance between the two concentric spheres is proportional to

[2005]
Q.322 Correct
Q.322 In-correct
Q.322 Unattempt
A wire fixed at the upper end stretches by length l by applying a force F. The work done in stretching is
[2004]
A wire fixed at the upper end stretches by length l by applying a force F. The work done in stretching is
[2004]
Q.323 Correct
Q.323 In-correct
Q.323 Unattempt
Spherical balls of radius ‘R’ are falling in a viscous fluid of viscosity ‘η’ with a velocity ‘v’. The retarding viscous force acting on the spherical ball is
[2004]
Spherical balls of radius ‘R’ are falling in a viscous fluid of viscosity ‘η’ with a velocity ‘v’. The retarding viscous force acting on the spherical ball is
[2004]
Q.324 Correct
Q.324 In-correct
Q.324 Unattempt
If two soap bubbles of different radii are connected by a tube
[2004]
If two soap bubbles of different radii are connected by a tube
[2004]
Q.325 Correct
Q.325 In-correct
Q.325 Unattempt
If the temperature of the sun were to increase from T to 2T and its radius from R to 2R, then the ratio of the radiant energy received on earth to what it was previously will be
[2004]
If the temperature of the sun were to increase from T to 2T and its radius from R to 2R, then the ratio of the radiant energy received on earth to what it was previously will be
[2004]
Q.326 Correct
Q.326 In-correct
Q.326 Unattempt
The temperature of the two outer surfaces of a composite slab, consisting of two materials having coefficients of thermal conductivity K and 2K and thickness x and 4x,respectively, are T2 and T1(T2>T1). The rate of heat transfer through the slab, in a steady state is(
A(T2T1)K
x
)
f
,
with f equal to

[2004]
The temperature of the two outer surfaces of a composite slab, consisting of two materials having coefficients of thermal conductivity K and 2K and thickness x and 4x,respectively, are T2 and T1(T2>T1). The rate of heat transfer through the slab, in a steady state is(
A(T2T1)K
x
)
f
,
with f equal to

[2004]
Q.327 Correct
Q.327 In-correct
Q.327 Unattempt
The earth radiates in the infra-red region of the spectrum. The spectrum is correctly given by
[2003]
The earth radiates in the infra-red region of the spectrum. The spectrum is correctly given by
[2003]
Q.328 Correct
Q.328 In-correct
Q.328 Unattempt
According to Newton's law of cooling, the rate of cooling of a body is proportional to (Δθ)n, where Δθ is the difference of the temperature of the body and the surroundings, and n is equal to
[2003]
According to Newton's law of cooling, the rate of cooling of a body is proportional to (Δθ)n, where Δθ is the difference of the temperature of the body and the surroundings, and n is equal to
[2003]
Q.329 Correct
Q.329 In-correct
Q.329 Unattempt
A cylinder of height 20 m is completely filled with water.
The velocity of efflux of water (in ms1) through a small hole on the side wall of the cylinder near its bottom is
[2002]
A cylinder of height 20 m is completely filled with water.
The velocity of efflux of water (in ms1) through a small hole on the side wall of the cylinder near its bottom is
[2002]
Q.330 Correct
Q.330 In-correct
Q.330 Unattempt
Heat given to a body which raises its temperature by 1°C is
[2002]
Heat given to a body which raises its temperature by 1°C is
[2002]
Q.331 Correct
Q.331 In-correct
Q.331 Unattempt
Infrared radiation is detected by
[2002]
Infrared radiation is detected by
[2002]
Q.332 Correct
Q.332 In-correct
Q.332 Unattempt
Which of the following is more close to a black body?
[2002]
Which of the following is more close to a black body?
[2002]
Q.333 Correct
Q.333 In-correct
Q.333 Unattempt
If mass-energy equivalence is taken into account, when water is cooled to form ice, the mass of water should
[2002]
If mass-energy equivalence is taken into account, when water is cooled to form ice, the mass of water should
[2002]
Q.334 Correct
Q.334 In-correct
Q.334 Unattempt
Two spheres of the same material have radii 1 m and 4 m and temperatures 4000 K and 2000 K respectively. The ratio of the energy radiated per second by the first sphereto that by the second is
[2002]
Two spheres of the same material have radii 1 m and 4 m and temperatures 4000 K and 2000 K respectively. The ratio of the energy radiated per second by the first sphereto that by the second is
[2002]
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