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A source of sound S emitting waves of fr...

A source of sound S emitting waves of frequency 100 Hz and an observer 0 are located at some distance from each other. The source is moving with a speed of `19.4 ms^(-1)` at an angle of `60^(@)` with the source observer line as shown in the figure. The observer is at rest. The apparent frequency observed by the observer (velocity of sound in air 330 `ms^(-1)`) is ......

A

97 Hz

B

100 Hz

C

103 Hz

D

106 Hz

Text Solution

Verified by Experts

The correct Answer is:
C

We have, `(f _(L))/( v + v _()) = (f _(S))/( v + v _(S))`
`therefore (f _(L))/( 330 + 0) = (100)/( 330 -9.7)`
`therefore f _(L) = 330 xx (100)/(320.3) = 103.03 Hz`
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KUMAR PRAKASHAN-WAVES-SECTION-E (Multiple Choice Questions (MCQs)) (MCQs asked in Gujarat Board and Competitive Exams)
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