Physics-
General
Easy
Question
A source of sound of frequency 256 Hz is moving rapidly towards a wall with a velocity of 5 m/sec. If sound travels at a speed of 330 m/sec, then number of beats per second heard by an observer between the wall and the source is:
- 7.7 Hz
- 9 Hz
- 4 Hz
- none of these
The correct answer is: none of these
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