Physics

Conversion of sound energy into electrical energy is done by microphone.

Infrared is used in night vision equipment when there is insufficient visible light to see. Night vision devices operate through a process involving the conversion of ambient light photons into electrons which are then amplified by a chemical and electrical process and then converted back into visible light.

An optical fiber is a cylindrical dielectric waveguide (nonconducting waveguide) that transmits light along its axis, by the process of total internal reflection.

A solid sphere rolls down two different inclined planes of the same height but of different inclinations. The speed and the of descend will be same.

By definition, superconductors are substances which display zero electrical resistance when a current is supplied, and are able to propagate such a current in a circuit indefinitely.

Glass is an insulator.

Suitable impurities are added to a semiconductor depending on its use. This is done in order to increase its electrical conductivity.

The loudness of sound is directly proportional to the amplitude of the wave. The loudness of the sound increases with increase in the amplitude vibration. The unit of loudness is decibel.

Of the following natural phenomena, mirage is known in Sanskrit as ‘deer’s thirst’?

Current = Charge/Time_x000D_ I = Q/t_x000D_ I = 1200/6_x000D_ I = 200 A.