JEE Mains · Physics · STD 11 - 14. waves and sound
Two sources of sound \(S_1\) and \(S_2\) produce sound waves of same frequency \(660\, Hz\). A listener is moving from source \(S_1\) towards \(S_2\) with a constant speed \(u\, m/s\) and he hears \(10\, beats/s\). The velocity of sound is \(330\, m/s\). Then, \(u\) equals ... \(m/s\)
- A \(15.0\)
- B \(10.0\)
- C \(5.5\)
- D \(2.5\)
Answer & Solution
Correct Answer
(D) \(2.5\)
Step-by-step Solution
Detailed explanation
\(f=660\,Hz,\) \(v=330\,m/s\) \(f_{1}=f\left(\frac{v-u}{v}\right) ; \quad f_{2}=f\left(\frac{v+u}{v}\right)\) \(\mathrm{f}_{2}-\mathrm{f}_{1}=\frac{\mathrm{f}}{\mathrm{v}}[\mathrm{v}+\mathrm{u}-(\mathrm{v}-\mathrm{u})]\)…
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