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प्रश्न
An echo-sounder in a trawler (fishing boat) receives an echo from a shoal of fish 0.4 s after it was sent. If the speed of sound in water is 1500 m/s, how deep is the shoal ?
विकल्प
150 m
300 m
600 m
7500 m
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उत्तर
Time taken to list the sent signal is 0.4 s.
Speed of sound in water is 1,500 m/s.
So,
= `(1500 xx 0.4)/2`
= 300 m
(b) 300 m.
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