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 \( \dfrac{1}{20}\)or 0.05 Hz?

Asked by Pragya Singh | 1 year ago |  118

1 Answer

Solution :-

(a) The speed of propagation is definite, it is equal to the speed of the sound in air. The wavelength and frequency will not be definite.

(b) The frequency of the note produced by a whistle is not \( \dfrac{1}{20}\) = 0.05 Hz. However, 0.05 Hz is the frequency of repetition of the short pip of the whistle.

Answered by Abhisek | 1 year ago

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