Question:medium
The pitch of whistle of an engine appears to drop by 30% of the original value when it passes a stationary observer. If speed of sound in air is \(350\text{ m/s}\), then the speed of engine in \(\text{m/s}\) is
The pitch of whistle of an engine appears to drop by 30% of the original value when it passes a stationary observer. If speed of sound in air is \(350\text{ m/s}\), then the speed of engine in \(\text{m/s}\) is
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Doppler:
Receding $\rightarrow$ frequency decreases
Updated On: May 8, 2026
- 87.5
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The Correct Option is A
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