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JEE Mains · Physics · STD 11 - 14. waves and sound
\(A\) and \(B\) are two sources generating sound waves. A listener is situated at \(C\) . The frequency of the source at \(A\) is \(500\,Hz\) . \(A,\) now, moves towards \(C\) with a speed \(4\,m/s.\) The number of beats heard at \(C\) is \(6.\) When \(A\) moves away from \(C\) with speed \(4\,m/s,\) the number of beats heard at \(C\) is \(18.\) The speed of sound is \(340\,m/s.\) The frequency of the source at \(B\) is ..... \(Hz\)
- A \(500\)
- B \(506\)
- C \(512\)
- D \(494\)
Answer & Solution
Correct Answer
(C) \(512\)
Step-by-step Solution
Detailed explanation
\(Case\, 1:\) When source is moving towards stationary listener apparent frequency \(\eta^{\prime}=\eta\left(\frac{\mathrm{v}}{\mathrm{v}-\mathrm{v}_{\mathrm{s}}}\right)\) \(=500\left(\frac{340}{336}\right)=506 \mathrm{Hz}\) \(Case\, 2:\) When source is moving away from the…
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