Q. Light Emitting Diodes (LED) is used in fancy electronic devices such as toys emit
? Visible light
Q. Optical fibre works on the
? Total internal reflection
Q. Light from the star, Alpha Centauri, which is nearest to the earth after the sun, reaches the earth in
? 4.2 years
Q. Supersonic plane fly with the speed
? Greater than the speed of sound
Q. Mach number is used in connection with the speed of
Q. Stars which appear single to the naked eye but are double when seen through a telescope are
Q. ML2T-2 is the dimensional formula for
? Couple acting on a body
Q. One watt-hour is equivalent to
? 3.6 x 103 J
Q. Sir C.V. Raman was awarded Nobel Prize for his work connected with which of the following phenomenon of radiation?
Q. In which of the following industries is mica as a raw material?