#VishnuPhysics Doppler’s Effect

Doppler Effect is the phenomenon of motion-related frequency change.
Consider if a vehicle is coming from very far off location as it approaches near our house, the sound increases and when it passes our house the sound will be maximum. And when it goes away from our house sound decreases.
This effect is known as Doppler Effect.
A person who is observing is known as Observer and object from where the sound wave is getting generated it is known as Source.
When the observer and source come nearer to each other as a result waves get compressed. Therefore wavelength decreases and frequency increases.
Case 1:- stationary observer and moving source
Let the source is at a distance L from the observer.
At any time t1, the source is at position S1.
Time taken by the wave to reach observer =L/v where v=speed of the sound wave.
After some time source moves to position S2 in time T0.
Distance between S1 and S2 =vsTo where vs is the velocity of the source.
Let t2be the time taken by the second wave to reach the o