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Let nr and nb be respectively the number of photons emitted by a red bulb and a blue bulb of equal power in a given time.
10-3 W of 5000 Å light is directed on a photoelectric cell. If the current in the cell is 0.16 mA, the percentage of incident photons which produce photoelectrons, is
If the frequency of light in a photoelectric experiment is doubled, the stopping potential will
The stopping potential for the photo electrons emitted from a metal surface of work function 1.7eV is 10.4 V. Identify the energy levels corresponding to the transitions in hydrogen atom which will result in emission of wavelength equal to that of incident radiation for the above photoelectric effect
When a photon of light collides with a metal surface, number of electrons, (if any) coming out is
A point source of light is used in photoelectric effect. If the source is removed farther from the emitting metal, the stopping potential
A point source causes photoelectric effect from a small metal plate. Which of the following curves may represent the saturation photocurrent as a function of the distance between the source and the metal?
The maximum kinetic energy of photoelectrons emitted from a surface when photons of energy 6 eV fall on it is 4eV. The stopping potential is Volts is
Radiation of two photon energies twice and five times the work function of metal are incident sucessively on the metal surface. The ratio of the maximum velocity of photoelectrons emitted is the two cases will be
Cut off potentials for a metal in photoelectric effect for light of wavelength l1, l2 and l3 is found to be V1, V2 and V3 volts if V1, V2 and V3 are in Arithmetic Progression and l1, l2 and l3 will be
In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.
Assertion (A): According to Rutherford, the atomic model, the path of electrons is parabolic.
Reason (R): Rutherford could not explain the stability of atoms.
Assertion (A): The binding energy per nucleon, for nuclei with mass number (A) > 56 decreases with A.
Reason (R): Nuclear force is weak in heavier nuclei.
Assertion (A): The isotopes are the atoms of the same element with different atomic masses. They require different positions in the periodic table.
Reason (R): Variable number of neutrons in the nuclei of the atoms of same elements leads to the different atomic masses.
In the mass number range A = 30 to 170, the binding energy per nucleon is
Cadmium rods are used in a nuclear reactor for
In what units is mass measured on the atomic scale?
Which of these statements about Bohr model applied to hydrogen atom correct?
An electron collides with a hydrogen atom in its ground state and excites it to a state of n = 3. How much energy was given to the hydrogen atom in this inelastic collision?
A triply ionized beryllium ion Be3+, (a beryllium atom with three electrons removed), behaves very much like a hydrogen atom except that the nuclear charge is four times as great. For the hydrogen atom, the wavelength of the photon emitted in the n =2 to n=1 to transition is 122 nm. What is the wavelength of the photon emitted when a Be3+ ion undergoes this transition?
In a semiconductor, current conduction is due to:
Electrons moving like molecules of gas exist in:
What is the value of the dielectric constant of air?
The essential distinction between X-rays and γ-rays is that:
The slope of frequency of incident light on stopping potential for a given surface will be
Ratio of the longest wavelengths corresponding to Lyman and Balmer series in hydrogen spectrum is
For photoelectric emission from certain metal, the cut-off frequency is ν. If radiation of frequency 2ν impinges on the metal plate, the maximum possible velocity of the emitted electron will be (m is the electron mass)
A parallel beam of fast moving electrons is incident normally on a narrow slit. A fluorescent screen is placed at a large distance from the slit. If the speed of the electrons is increased, then which of the following statements is correct?
In the Young's double-slit experiment, the intensity of light at a point on the screen (where the path difference is λ) is k, (λ being the wavelength of light used). The intensity at a point where the path difference is λ/4 will be
When the energy of the incident radiation is increased by 20%, the kinetic energy of the photoelectrons emitted from a metal surface increases from 0.5 eV to 0.8 eV. The work function of the metal is
If the kinetic energy of the particle is increased to 16 times its previous value, the percentage change in the de-Broglie wavelength of the particle will be
Hydrogen atom in ground state is excited by a monochromatic radiation of λ = 975 Å. The number of spectral lines in the resulting spectrum emitted will be
We have a source of red light and blue light of same power. Then the red light gives photons per second:
If there were no atmosphere, the earth would have been
A radiation of energy 'E' falls normally on a perfectly reflecting surface. The momentum transferred to the surface is (C = Velocity of light)
A certain metallic surface is illuminated with monochromatic light of wavelength λ. The stopping potential for photoelectric current for this light is 3V0. If the same surface is illuminated with a light of wavelength 2λ, the stopping potential is V0. The threshold wavelength for this surface for photoelectric effect is
We wish to see inside an atom. Assume the atom to have a diameter of 100 pm. This means that one must be able to resolve a width of say 10 pm. If an electron microscope is used, the energy required should be
The half-life of 131I is 8 days. If we have a sample of 131I at time t = 0, we can assert that
If an electromagnetic radiation has an energy of 13.2 keV, then the radiation will belong to the region of
A freshly prepared radioactive source of half-life 2 hours emits radiation of intensity which is 64 times the permissible safe level. The minimum time after which it would be possible to work safely with this source is
A heavy nucleus at rest breaks into two fragments, which fly off with velocities in the ratio of 8 : 1. The respective ratio of the radii of the fragments (assumed spherical) is
In the fission of one part of uranium, if 0.5 gm mass is decayed, then how much energy (in kWh) will be obtained?
The distance of closest approach of an alpha particle fired at a nucleus with momentum p is r0. The distance of closest approach when the alpha particle is fired at the same nucleus with momentum 2p will be
In the following question, two statements are given. One is assertion and the other is reason. Examine the statements carefully and mark the correct answer according to the instructions given below.
Assertion (A): Nuclear forces arise from strong Coulombic interactions between protons and neutrons.
Reason (R): Nuclear forces are independent of the charge of the nucleons.
Activity of a radioactive sample decreases to (1/3)rd of its original value in 3 days. Then, in 9 days, its activity will become
The material used for making thermionic cathode must have
The general formula CnH2nO2 could be for open chain
Which of the following methods/reactions is used for the preparation of pure methane?
How many total cyclic isomers are possible for C5H10 ?
What is the IUPAC name of the following compound?
Compounds (A) and (B) are soluble in water near to its boiling point. If the solubility of (A) is 2 g per 100 ml of water and the solubility of (B) is 4 g per 100 ml, then the name of method to separate (A) and (B) from their mixture is:
The nature of the products formed in the following reactions is:
An aqueous solution of compound A gives ethane on electrolysis. The compound A is
Consider the resonating structures of prop-2-enal.
The correct decreasing order of stability of the given resonating structures is:
In the following question, two statements are given. One is assertion and the other is reason. Examine the statements carefully and mark the correct answer accordingly.
Assertion: p-O2N – C6H5COCH3 is prepared by Friedel-Craft's acylation of nitrobenzene.
Reason: Nitrobenzene easily undergoes electrophilic substitution reaction.
With ammoniacal cuprous chloride solution, a reddish brown precipitate is obtained on treating with
In the following questions a statement of Assertion (A) followed by a statement of Reason (R) is given. Choose the correct option out of the choices given below each question.
Assertion (A): Pent-1-ene and pent-2-ene are position isomers.
Reason (R): Position isomers differ in the position of functional group or substituent.
Heterolytic cleavage is a way to cleave the:
The correct order of bond energies of the following bonds is:
(I) C(sp3)-C(sp3), (II) C(sp2)-C(sp2), (III) C(sp)-C(sp)
In the following question, two statements are given. One is Assertion and the other is Reason. Examine the statements carefully and mark the correct answer according to the instructions given below.
Assertion: Trans-2-butene on reaction with Br2 gives meso-2, 3-dibromobutane.
Reason: The reaction involves syn-addition of bromine.
Producer gas is
Ethylene oxide, when treated with Grignard reagent, yields
Which of the following compounds will exhibit geometrical isomerism?
The alkene which on reaction with HBr follows Markovnikov rule is:
Which of the following ions is most stable?
On mixing certain alkane with chlorine and irradiating it with ultraviolet light, it forms only one monochloro alkane. The alkane could be
This section contains 5 multiple choice questions. Each question has four choices (a), (b), (c), and (d), out of which ONE or MORE THAN ONE is correct.
Consider the following molecule
The correct statement concerning the above molecule is/are
The compound that has the lowest boiling point is:
Which of these nitrogenous compounds has the most nucleophilic nitrogen?
Lassaigne's test is used to detect the presence of elements such as nitrogen, sulphur and halogens with the help of Sodium Fusion Extract. Out of the given samples, the one that would fail to give positive Lassaigne's test is:
Pick out the wrong statement.
The lowest alkene which is capable of exhibiting geometrical isomerism is
Which of the following is not a nucleophile?
In the formation of which of the following compounds, only sp and sp2 hybrid orbitals are involved?
When 3,3-dimethyl-2-butanol is heated with H2SO4, the major product is
Which of the following groups does not have priority over formyl (-CHO) group in nomenclature?
Assertion: Cyclopentadienyl anion is much more stable than allyl anion.
Reason: Cyclopentadienyl anion is aromatic in character.
Acetylene and dil. H2SO4 react to produce:
What is the name of the reaction given below?
In the reaction
Y is
Assertion: CH4 does not react with CI2 in the dark.
Reason: Chlorination of CH4 takes place only in the presence of sunlight.
Which of the following statements is/are correct regarding the below compound?
Which of the following carbocations is the least stable?
In the following question, two statements are given. One is Assertion, and the other is Reason. Examine the statements carefully and mark the correct answer according to the instructions given below.
Assertion: Neopentane forms one mono-substituted compound.
Reason: Neopentane is an isomer of pentane.
Assertion (A): Simple distillation can help in separating a mixture of propan-1-ol (boiling point 97°C) and propanone (boiling point 56°C).
Reason (R): Liquids with a difference of more than 20°C in their boiling points can be separated by simple distillation.
Arrange the following compounds in decreasing order of acidity:
Which of the following statements is/are incorrect for alkanes?
A. All C-H and C-C bonds are of lengths 1.12 Å and 1.54 Å, respectively.
B. All bond angles are tetrahedral, having a value of 109°28' or 109.5°.
C. The C-C chain is linear and not zigzag.
D. All alkanes exhibit isomerism.
In which of the following halogen addition reactions, racemic mixture of products is formed?
Consider the following reaction.
Molecular formula of both P and Q are C6H13l
tetra substituted alkene isom er of A. Hence, P is most likely
Match the following:
Label the part marked by the blue arrow.
How do the top three layers assist in developing anthers?
Following the establishment of the endosperm, ___ split.
Identify “A” and “B” in the T.S of mature anther:
How many meiotic divisions are required to form 64 pollen grains?
Filiform apparatus present at micropylar part of the Synergids help in:
What happen to haploid megaspores formed by megaspore mother cell in an angiospermic plant?
Assertion: The innermost layer of microsporangium is called tapetum.
Reason: Tapetum performs the function of protection and help in dehiscence of anther to release pollen grains.
A bilobed dithecous anther had 50 microspore mother cells per microsporangium. How many male gametes this anther can produce?
Pollen grain of large number of species can be stored in:
In nature, inbreeding and out breeding of plants is regulated by------?
Continued self-pollination results in inbreeding depression as they------?
Abundant occurrence of fossilized pollen grain is due to resistant:
At the _______ end, embryogenesis happens.
The correct sequence of parts of female reproductive organ in plants
If an endosperm cell of angiosperm contain 24 chromosome, the number of chromosome in each cell of root is?
The meiocyte of an onion plant contains 32 chromosomes. Calculate the number of chromosomes found in its endosperm?
Epiblast present in certain monocot embryo represents--------?
A typical angiospemic embryo sac is though 8 nucleate is 7-celled. 8 nuclei includes______.
The major approach towards the crop improvement programme is______.
Which of the following parts of a plant take part in sexual reproduction?
In which of the following plants fruit contain larger number of seed?
Dormancy is the____.
Which of the following walls of microsporangium has more than one nucleus per cell?
During germination, a seedling develops from a/an
Which of the following cells undergoes meiotic division?
a. Microspore mother cell
b. Megaspore mother cell
c. Sporogenous cells
d. Microspores
Besides cellulose, the intine layer of pollen grains also contains
Perisperm is a residual nucellus, which persists in some seeds. In which of the following plants it is found?
Which of the following flowers is a bisexual, homogamous and pollination takes place in it prior to its opening?
The number of ovules in an ovary may be one or many. In which of the following plants a single ovule might be present in the ovary?
Which of the following is an aquatic plant that does not use water for pollination?
By which kind of pollination method can assured seeds be produced even in the absence of pollinators?
What is the ratio of antipodal cells: polar cell: synergids in embryo sac?
Which of the following sentences about megasporogenesis is false?
Apomixis is a phenomenon found in some grasses. What happens during apomixis?
Microsporangium is generally surrounded by _____ wall layers and the layer that performs the function of providing nutrition to pollen is ______.
Where can pollen from multiple species be preserved?
Through which cell of the embryo sac does the pollen tube enter the embryo sac?
The coconut water from tender coconut represents
Milky water in green coconut is:
Perisperm is:
Identify the parts marked 1, 2, 3 and 4 in the diagram given below.
If there are 100 microspore mother cells in an anther, the number of tetrads formed will be:
Which statement is not correct?
In human females, meiosis-ll is not completed until?
In a pregnant woman having prolonged labour pains, if the childbirth has to be hastened, it is advisable to administer a hormone that can
The body of sperm is covered by _______
What part of sperm holds the haploid chromatin?
Spermatogenesis and sperm differentiation are under the control of
Sugar fructose is present in the secretion of
The number of egg cells produced as a result of meiosis in humans is
How many eggs will be formed from 100 primary oocytes
A hormone secreted by the posterior lobe of the pituitary is concerned with
In the human being, developing embryo remains in
Corpus luteum is
Which of the following statements are related to Bartholin's gland?
Proliferative phase of menstrual cycle is also called
Which of the following forms the birth canal?
Menstrual cycle occurs in
Identify the human development stage shown below as well as the related right place of its occurrence in a normal pregnant woman and select the right option for the two, together
Given below are four statements (i)-(iv) regarding embryonic development in humans.
(i) Cleavage divisions bring about considerable increase in the mass of protoplasm.
(ii) With more cleavage divisions, the resultant blastomeres become smaller and smaller.
(iii) The blastomeres in the blastocyst are arranged into two layers, trophoblast and endometrium.
(iv) Cleavage divisions result in a solid ball of cells called morula.
Which of the above two statements are correct?
In spermatogenesis, reduction division of chromosome occurs during the conversion of
Seminal plasma in humans is rich in
Which of the following events is correctly matched with the time period in a normal menstrual cycle?
Which set is similar?
Ovulation takes place in a month between
The bulbourethral glands in males are also known as:
Spermatogenesis begins during puberty due to the increased secretion of
Secondary spermatocytes and spermatids are
The yellow-coloured first milk that comes out from the mother's mammary glands, just after the child birth, is
During gametogenesis, how many sperms and ova will be produced from 25 primary spermatocytes and 25 primary oocytes, respectively?
Which one of the following is not the function of placenta?
Which of the following is untrue about the menstrual cycle?
Select the correct option describing gonadotropin activity in a normal pregnant female.
The sixth month of normal pregnancy is accompanied by
Regeneration of endometrium through proliferation of uterine and fallopian tube cells occurs at
The vas deferens receives duct from the seminal vesicle and opens into urethra as
All of the following are haploid, except
Which of the following characterises the ampulla of the fallopian tube?
The maximum contribution to semen is made by
Second meiotic division during spermatogenesis leads to the formation of
In which of the following anatomical structures are ciliated epithelium most numerous?
If the vas deferens of a man is surgically blocked,
Changes occurring in the uterus during the post-menstrual phase are governed by
Menstrual flow occurs due to lack of
Zona pellucida is a membrane of egg. It is the
During organogenesis, pineal glands develop from a layer which also gives rise to
During the gestation period, the end of twenty weeks of the fetus is characterised by
Greater vestibular glands in females are homologous to which of the following in males?
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tetra substituted alkene isom er of A. Hence, P is most likely
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