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A soldier walks towards a high wall taki...

A soldier walks towards a high wall taking 120 steps per minute. When he is at a distance of 90 m from the wall he observes that echo of step coincides with the next step. The speed of sound must be

A

340 m/s

B

330 m/s

C

300 m/s

D

360 m/s

Text Solution

Verified by Experts

The correct Answer is:
D
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