Question

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?

Answer 1

(a) A short pip be a whistle has neither a definite wavelength nor a definite frequency. However, its speed of propagation is fixed, being equal to speed of sound in air.
(b) No, frequency of the note produced by a whistle is not 1/20 = 0.05 Hz. Rather 0.05 Hz is the frequency of repetition of the short pip of the whistle.