JEE Mains · Physics · STD 11 - 14. waves and sound
Two factories are sounding their sirens at \(800\, Hz\) . A man goes from one factory to other at a speed of \(2\,m/s\). The velocity of sound is \(320\, m/s\). The number of beats heard by the person in one second will be
- A \(2\)
- B \(4\)
- C \(8\)
- D \(10\)
Answer & Solution
Correct Answer
(D) \(10\)
Step-by-step Solution
Detailed explanation
Given: Frequency of sound produced by siren, \(f=800 \mathrm{Hz}\) Speed of observer, \(u=2 \mathrm{m} / \mathrm{s}\) Velocity of sound, \(v=320 \mathrm{m} / \mathrm{s}\) No. of beats heard per second \(=?\) No. of extra waves received by the observer per second…
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