Learn Top 20 Physics questions

Q&A 1. Energy of the Sun is generated by – Nuclear fusion 

Q&A 2. When the TV is switched on,- Visualization starts immediately, but audio is heard later, because sound travels at a lower velocity than light.

Q&A 3. Which principle is used to produce minimum temperature – superconductivity

Q&A 4. The source of renewable energy in stars is due to – conversion of hydrogen into helium

Q&A 5. Which metal is used as a semiconductor in transistor - Germanium

Q&A 6. Which is used by the TV remote control unit to operate a TV set – Microwaves

Q&A 7. Doordarshan signals cannot be received after a certain distance because the surface of the earth is curved.

Q&A 8. Television signals are generally not received by TV sets after a certain distance, because of the curvature of the earth

Q&A 9. Radar is used for – To locate and guide ships, aircrafts etc.

Q&A 10. Three dimensional picture is taken by – Holography

Q&A 11. Laser beam is used in – kidney therapy

Question and Answer 12. The phenomenon associated with the formation of a three dimensional image by the interference of two light rays emanating from a laser or a coherent light source is called - holography

Q&A 13. Laser ray is – of only one color

Q&A 14. Atoms which have the same number of protons but different number of neutrons are called - isotopes

Q&A 15. The process of breaking a heavy nucleus into two lighter nuclei is called – Nuclear Fission

Q&A 16. Hydrogen bomb is based on – Nuclear fission

Q&A 17. A jet aircraft is flying in the air with a velocity of Mach 2. When the speed of sound is 332 m/s then what is the speed of the aircraft – 664 m/s

Q&A 18. In which medium the speed of sound will be maximum at a temperature of about 200C - Iron

Q&A 19. A biological method in which ultrasonic sound is used – Sonography

Q&A 20. Which wave cannot propagate in zero - sound