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प्रश्न
The frequencies of four sound waves are given below. Which of these sound waves can be used to measure the depth of sea by the echo method ?
विकल्प
15,000 Hz
10 kHz
50 kHz
10,000 Hz
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उत्तर
Depth of sea can be measured using ultrasonic waves.
(c) 50 kHz.
संबंधित प्रश्न
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Assertion: The sound which we hear again is called Echo.
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