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JEE Mains · Physics · STD 11 - 14. waves and sound

A source of sound \(A\) emitting waves of frequency \(1800\,Hz\) is falling towards ground with a terminal speed \(v.\) The observer \(B\) on the ground directly beneath the source receives waves of frequency \(2150\,Hz.\) The source \(A\) receives waves, reflected from ground of frequency nearly ..... \(Hz\) (Speed of sound \(= 343\,m/s\) )

  1. A  \(2150\)
  2. B  \(2500\)
  3. C  \(1800\)
  4. D  \(2400\)
Verified Solution

Answer & Solution

Correct Answer

(B)  \(2500\)

Step-by-step Solution

Detailed explanation

Given \(f_{A}=1800 \mathrm{Hz}\) \({v_{t}=v}\) \({f_{B}=2150 \mathrm{Hz}}\) Reflected wave frequency received by \(A.\) \(f_{A}^{\prime}=?\) Applying doppler's effect of sound, \(f^{\prime}=\frac{v_{s} f}{v_{s}-v_{t}}\) Here,…