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प्रश्न
State the use of echo by a bat, dolphin and fisherman.
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उत्तर
Bats, dolphin and fisherman detect their enemies or obstacles or position of fish by emitting/sending the ultrasonic waves and hearing/detecting the echo.
संबंधित प्रश्न
A wire of length 80 cm has a frequency of 256 Hz. Calculate the length of a similar wire under similar tension, which will have frequency 1024 Hz
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The following diagram shows three ways in which the string of an instrument can vibrate.

(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)?
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