The frequency of echo will be_________Hz if the train bellowing a whistle of frequency 320 Hz is moving with a velocity of 36 km/h towards a hill from which an echo is heard by the train driver. Velocity of sound in air is 330 m/s.

A set of 16 tuning forks are so arranged that each produce 4 beats with the previous one. If the frequency of last tuning fork is double that of first, the frequency of third tuning fork is

A pipe open at both ends produces a note of fundamental frequency V₁. When the pipe is kept with (1/3)^rd of its length in water, it produces a note of frequency V₂.The value of V₁/ V₂ is

A string of linear density 0.4 kg/m is stretched with force of 1000 N. A transverse wave is set up along it. The speed of the wave is

A particle is executing S.H.M. its potential energy v/s displacement graph is given by

The value of restoring force constant is :-

A heavy rope is suspended from rigid support. A wave pulse is set up at the lower end. Then