The First Law of Thermodynamics states that heat is a form of energy, and thermodynamic processes are therefore subject to the principle of conservation of energy. This means that heat energy cannot be created or destroyed. It can, however, be transferred from one location to another and converted to and from other forms of energy.

OTE, Ocean thermal Energy, is the form of renewable energy- which involves tapping the temperature difference in the surface and deeper ocean, for the production of energy.

Mica is a raw material of electrical industries.

The raw materials needed to produce cement (calcium  carbonate, silica, alumina and iron ore) are generally extracted from limestone rock, chalk, clayey schist or clay.

Raw materials to the industrial ceramics and glass industries, including such materials as clay, silica, alumina, feldspar, metallic oxides

• Fiber-optic communication is a method of transmitting information from one place to another by sending pulses of light through an optical fiber.


• In an optical fibre the signal is transmitted due to total internal reflection.

Half-duplex data transmission means that data can be transmitted in both directions on a signal carrier, but not at the same time.

The swinging of pendulum of a clock is an oscillating motion. A pendulum is a weight suspended from a pivot so that it can swing freely. 
There are four basic types of motion in mechanical systems: 

(a) Rotatory motion 

(b) Linear motion 

(c) Reciprocating motion 

(d) Oscillating motion

X-radiation (composed of X-rays) is a form of electromagnetic radiation. Most X-rays have a wavelength ranging from 0.01 to 10 nanometers, corresponding tofrequencies in the range 30 petahertz to 30 exahertz (3×10¹⁶ Hz to 3×10¹⁹ Hz) and energies in the range 100 eV to 100 keV. X-ray wavelengths are shorter than those of UV rays and typically longer than those of gamma rays. In many languages, X-radiation is referred to with terms meaning Röntgen radiation, afterWilhelm Röntgen, who is usually credited as its discoverer, and who had named itX-radiation to signify an unknown type of radiation. Spelling of X-ray(s) in the English language includes the variants x-ray(s), xray(s), and X ray(s).

• Raindrops form spherical structure due to the surface tension of water.
• This surface tension makes the molecules stick together. 
• The inward forces on the surface molecules of the liquid droplet tend to cause the surface to volume ratio as small as possible.

Variation of g- 

a) Gravity g decreases with height 

b) Gravity g is maximum at poles 

c) Gravity g is minimum at equator 

d) Gravity g decreases due to rotation of the earth

All of the given statements are true.

The angle in which a cricket ball should be hit to travel maximum horizontal distance is 45^o with the horizontal