wave_mechanics critical_thinking Question 14
Question: Two whistles A and B produces notes of frequencies 660 Hz and 596 Hz respectively. There is a listener at the mid-point of the line joining them. Now the whistle B and the listener start moving with speed 30 m/s away from the whistle A. If speed of sound be 330 m/s, how many beats will be heard by the listener
[RPET 1996]
Options:
A) 2
B) 4
C) 6
D) 8
Show Answer
Answer:
Correct Answer: B
Solution:
For observer note of $ B $ will not change due to zero relative motion.
Observed frequency of sound produced by A = $ 660\frac{(330-30)}{330}=600Hz $
$ \therefore $ No. of beats = 600 ? 596 = 4
BETA
