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A car moving towards a cliff emits sound of frequency 'n'. If the difference in frequencies of the horn and its echo heard by the driver of the car is 10% of 'n', then the speed of the car is nearly (Speed of sound in air is 336ms$^{-1}$)
A car moving towards a cliff emits sound of frequency 'n'. If the difference in frequencies of the horn and its echo heard by the driver of the car is 10% of 'n', then the speed of the car is nearly (Speed of sound in air is 336ms$^{-1}$)
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Problems involving echoes and the Doppler effect can be treated as a two-step process. First, the moving object is the source and the stationary reflector is the observer. Second, the reflector becomes a stationary source emitting the received frequency, and the original object is now a moving observer.
Updated On: Mar 30, 2026
- 16 ms$^{-1}$
- 18 ms$^{-1}$
- 30 ms$^{-1}$
- 33 ms$^{-1}$
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The Correct Option is A
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