Question

What is frequency of whistle heared by a man running towards engine with speed 10m/s?
The true frequency of the whistle is 400Hz.and speed of sound is 340m/s.

Answer 1

Dear Student,

this is the question of doppler effect.
$$\begin{gathered} apparentfrequencyf\text{'}=f\frac{V+10}{V}=400\frac{350}{340}=411.76Hz \\ Regards \end{gathered}$$