31.  Which atmospheric Layer is used for the transmission of radio waves?

32.  A body in uniform motion with uniform speed-

33.  According to special theory of relativity the mass of a particle -

34.  Humidity is measured by -

35.  Ball pen act on the principle of -

36.  Flywheel is an important part of a steam engine because

37.  The spoon dropped by an astronaut in a satellite will

38.  Anemometer is used to measure-

39.  Lubricant oil is used in vehicle to -

40.  Mechanical energy is countered into electrical energy

41.  Who discovered X-Rays?

42.  A TV channel characterized by -

43.  The process by which sunlight reaches to earth--..

44.  X-rays are ----------.. waves.

45.  The danger signals are red while the eye is more sensitive to yellow because.