A train whistle is 580 Hz when stationary. It is coming toward you at 18.8 m/s. What frequency do you hear? (Speed of sound = 343 m/s) (Unit=Hz)

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asked Sep 9, 2021 182k views

2 Answers

Chang Chung · Answer 1 · 2021-09-15T04:44:32+0000

Answer:

612 Hz.

Explanation:

The frequency of the sound will be proportionally higher when coming towards you. The increase is related to the speed of the train.

So the frequency will be:

580 + (580 / 343) * 18.8

= 612 Hz.

This is called the Doppler effect.