Question

A man runs towards a source at $10{\text{ms}}^{-1}$. The frequency of the second produced by the source is 400 Hz and heard is $410\text{Hz.}$ The speed of the sound perceived by the man will be

• A. $330{\text{ms}}^{-1}$
• B. $400{\text{ms}}^{-1}$
• C. $350{\text{ms}}^{-1}$
• D. $340{\text{ms}}^{-1}$

Answer 1

Answer: (B)

$400{\text{ms}}^{-1}$

$n^{\prime }=\frac{V+V_o}{V}n$

$410=\frac{V+10}{V}400$

$V=400m{s}^{-1}$

option "B" is correct.