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General
Easy
Question
An engine is moving on a circular track with a constant speed. It is blowing a whistle of frequency 500 Hz. The frequency received by an observer standing stationary at the centre of the track is
- 500 Hz
- More than 500 Hz
- Less than 500 Hz
- More or less than 500 Hz depending on the actual speed of the engine
The correct answer is: 500 Hz
Since there is no relative motion between the source and listener, So apparent frequency equals original frequency
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