A star which is emitting radiation at a wavelength of 5000 is approaching the earth with a velocity of 1.50 x10⁶ m/s. The change in wavelength of the radiation as received on the earth is

With the propagation of a longitudinal wave through a material medium, the quantities transmitted in the propagation direction are

Equations of two progressive waves are given by 

If amplitude and time period of resultant wave are same as that of both the waves, then 

A pulse of a wave train travels along a stretched string and reaches the fixed end of the string.  It will be reflected back with

The equation of a wave is given by

where x and y are in metre and t in second, then velocity of wave is

The phase difference between two waves represented by

where x is expressed in metre and t is expressed in second, is approximately

Which one of the following statements is true ?

A standing wave is represented by y =a sin (100t ) cos (0.01)x, where y and a are in millimetre, t in second and x is in metre.  Velocity of wave is

A vehicle, with a horn of frequency n is moving with a velocity of 30 m/s in a direction perpendicular to the straight line joining the observer and the vehicle.  The observer perceives the sound to have a frequency n + n₁.  Then (If the sound velocity in air is 300 m/s)

Two strings A and B have lengths l_A and l_B and carry masses M_A and M_B at their lower ends, the upper ends being supported by rigid supports.  If n_A and n_B are the frequencies of their vibrations and n_A = 2n_B, then