Dudecue an expression for apparent frequency of sound,when the listener moves towards a stationary source.

A train whistling while approaching a railway platform with a speed of 90 km(s)^-1 .The frequency of sound of the whistle is 600 Hz.If the velocity of sound in air is 325 m(s)^-1 ,calculate the apparent frequency of the sound of the whistle as heard by an observer standing on the platform.

Find expression for Doppler effect in case of a moving source when the observer is at rest and there is no wind.

Deduce the expression for instantaneous power supplied to a capacitor when the capacitor is connected to an ac source.

A source of sound is movig with a speed 220 m(s)^-1 towards a stationary target.While moving,it emits a wave of frequency 1000 Hz.Some of the sound reaching the target get reflected back to the source as echo.Calculate the (i)frequency of sound as detected by the target and (ii)the frequency of echo as detected by the source?

At each of the stations A and B a siren its surrounding with a constant of frequency pf 250 Hz.A cyclist from A proceeds towards B with a velocity 12km/hr and hears 5 beats per second.Calculate the velocity of sound.

A siren is fitted on a car going towards a vertical wall at a speed of 36 kmh^(-1) . A person standing on the ground behind the car, listeners to the siren sound coming directly from the source as well as that coming after reflection from the wall. Calculate the apparant frequencies of both the sounds. Velocity of sound 340ms^(-1) , frequency of the siren 500Hz.

The frequency of a source of sound is 100 Hz. How money times does it vibrate in a minute?

Four sources emit sound waves of four different frequencies . Which one can not be heard?

What percentage of K.E. of moving particle is transferred to a stationary particle when it strike the stationary particle of 4 times its mass.

When a sound is reflected from a distant object, an echo is produced. Let the distance between the reflecting surface and the source of sound production remains the same. Do you hear echo sound on a hotter day?