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A tuning fork of frequency 90 Hz is soun...

A tuning fork of frequency `90 Hz` is sounded and moved towards an observer with a speed equal to one - tenth the speed of sound. The note heard by the observer will have a frequency

A

`100`

B

`110`

C

`80`

D

`70`

Text Solution

Verified by Experts

The correct Answer is:
A

`{:(rarr v_(s) = v//10,,larr v_(o) = 0),(overset(*)(S),overset(v)rarr,overset(*)(O)):}`
`f' = f((v)/(v-v_(s))) = 90((v)/(v-v//10)) = 100 Hz`
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Knowledge Check

  • A source of sound emitting a note of frequency 90 Hz moves towards an observer with speed equal to ( (1)/( 10 ) )^(th ) of velocity of sound.The frequency of the note heard by the observer will be

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    90 Hz
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