Q 11-14-055JEE MainJEE Main 2023 (25 Jan, Shift 2)Easy
A train blowing a whistle of frequency $320\ \text{Hz}$ approaches an observer standing on the platform at a speed of $66\ \text{m s}^{-1}$. The frequency observed by the observer will be (given speed of sound $=330\ \text{m s}^{-1}$) ______ Hz.
Numerical value type. Enter your answer.
Answer: 400
$$f'=f\frac{v}{v-v_s}=320\times\frac{330}{264}=400\ \text{Hz}$$
Solution by Sreeraj P, M.Sc Physics