11. If the electrical resistance of a typical substance suddenly drops to zero, then the substance is called: Super conductor

12. If there is no atmosphere the length of the day would:
Decrease

13. In which date India’s Chandrayan was launched:
2008 October 22

14. Kaleidoscope is based on the principle of: Multiple
Reflection

15. Magnetic field of electric current was discovered by:
Oesterd

16. Magnetism at the centre of a bar magnet is: Zero

17. Materials for rain-proof coats and tents owe their water proof properties to: Surface tension

18. Name the inventor of Black Box Flight recorder: David Warren

19. Noise is measured in: Decibel

20. Nuclear sizes are expressed in:

Fermi