A narrow sound pulse (for example, a short pip by a whistle) is sent across a medium.
i. Does the pulse have a definite (a) frequency, (b) wavelength, (c) speed of propagation?
ii. If the pulse rate is 1 after every 2s, (that is the whistle is blown for a split of second after every 20s), is the frequency of the note produced by the whistle equal to 1/20 or 0.05 Hz?
Answer:
i. A short pip by a whistle
a. Will not have fixed wavelength.
b. Will not have a fixed frequency.
c. Will have definite speed that will be equal to speed of sound in air.
ii. 0.05 Hz will be the frequency of repetition of the short pip.