Thermal electricity is generated by using which of these ?
1). Coal only
2). Coal and Natural Gas
3). Coal, Natural Gas and Petroleum
4). None of these
2. Bolometer is used to measure
4. For photoelectric effect to take place, the metal used as the cathode should have ________
5. Among the following materials sound travels fastest in
6. An aircraft can perform aerobatic manoeuvres in a vertical loop because of
7. The substance which conducts current in the solid state is
8. What is colour of light related to?
10. To an observer on thearth the stars appear to twinkle. This can be described to