A submarine emits a sonar pulse, which returns from an underwater cliff in 1.02 s. If the speed of sound in salt water is 1531 m/s, how far away is the cliff?
Time taken by the sonar pulse to return, t = 1.02 s
Speed of sound in salt water, v = 1531 m/s
Total distance covered by the sonar pulse = Speed of sound × Time taken
Total distance covered by the sonar pulse = 1.02 x 1531 = 1561.62 m ....(i)
Let d be the distance of the cliff from the submarine.
Total distance covered by the sonar pulse = 2d
⇒ 2d = 1561.62 [From (i)]
⇒ d = 780.81 m
⇒ 2d = 1561.62
d = 780.81 m
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