Question

A narrow sound pulse (for example, a short pip by a whistle) is sent across a medium. 

1. Does the pulse have a definite (i) frequency, (ii) wavelength, (iii) speed of propagation? 

2. 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

1. The pulse does not have definite frequency and definite wavelength but has definite speed of propagation. 

2. The frequency of the note is not 1/20 Hz or 0.05 Hz. It is only the frequency of repetition of the whistle.