Question
Explain the Doppler's effect.
✓
Answer
Whenever there is a relative motion between a source of sound and the listener, the apparent frequencies of sound heard by the listener is different from the actual frequency of sound emitted by the source.
For sound the observed frequency v' is given by
$\text{v}'=\Big(\frac{v+v_0}{v+v_\text{s}}\Big)\text{v}$
For sound the observed frequency v' is given by
$\text{v}'=\Big(\frac{v+v_0}{v+v_\text{s}}\Big)\text{v}$
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