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प्रश्न
Explain how is the principle of echo used by
(a) The bat during its flight at night,
(b) The dolphin to locate small fish as its prey.
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उत्तर
(a) Bats can produce and detect the sound of very high frequency. The bats fly with speed much lower than the speed of sound. The sounds produced by flying bats get reflected from any obstacle in front of it. By hearing the echoes, bats come to know where the obstacles are, even in the dark. So, they can fly safely without colliding with the obstacles. This process of detecting obstacles is called sound ranging.
(b) Dolphins detect their enemies and small fishes by emitting ultrasonic waves in all directions and then hearing their reflected sound i.e. echo. Dolphins can judge the nature of obstacles or of small fish by hearing the echo and catch their prey.
संबंधित प्रश्न
A wave passes from one medium to another medium. Mention one property of the wave out of speed, frequency or wavelength which changes.
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(a) which of the diagram shows the principal note?
(b) which has the frequency four times that of the first?
(c) what is the ratio of the frequency of the vibration in (i) and (ii)?
Explain how the principle of echo is used by
The dolphin to locate small fish as its prey
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