JEE Mains · Physics · STD 11 - 14. waves and sound
A train blowing a whistle of frequency \(320\,Hz\) approaches an observer standing on the platform at a speed of \(66\,m / s\). The frequency observed by the observer will be (given speed of sound \(=330\,ms ^{-1}\) ) \(.............Hz\).
- A \(320\)
- B \(400\)
- C \(300\)
- D \(180\)
Answer & Solution
Correct Answer
(B) \(400\)
Step-by-step Solution
Detailed explanation
\(f_{a p p}=f\left(\frac{v}{v-v_s}\right)\) \(=320\left(\frac{330}{330-66}\right)\) \(=400\,Hz\)
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