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Question
In a submarine equipped with sonar, the time delay between the generation of a pulse and its echo after reflection from an enemy submarine is observed to be 80 s. If the speed of sound in water is 1460 ms-1. What is the distance of an enemy submarine?
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Solution
Given:
Speed of sound in water = 1460 ms-1
Time delay = 80s
Distance of enemy ship = ?
Solution:
Total distance covered = speed × time
= 1460 ms-1 × 80s = 116800 m
Time taken is for forwarding and backward path of sound waves.
Distance of enemy ship = `"total distance covered"/2 = 116800/2`m
= 58400 m (or) 58.4 km
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