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प्रश्न
The engine of a train sounds a whistle at frequency v. The frequency heard by a passenger is
पर्याय
\[> v\]
\[< v\]
\[= \frac{1}{v}\]
\[= v\]
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उत्तर
\[= v\]
For the Doppler effect to occur, there must be relative motion between the source and the observer. However, this is not the case here. Hence, the frequency heard by the passenger is υ.
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संबंधित प्रश्न
A narrow sound pulse (for example, a short pip by a whistle) is sent across a medium. (a) Does the pulse have a definite (i) frequency, (ii) wavelength, (iii) speed of propagation? (b) If the pulse rate is 1 after every 20 s, (that is the whistle is blown for a split of second after every 20 s), is the frequency of the note produced by the whistle equal to 1/20 or 0.05 Hz
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