wave_mechanics dopplers_effect Question 38
Question: A source of sound and listener are approaching each other with a speed of 40 m/s. The apparent frequency of note produced by the source is 400 cps. Then, its true frequency (in cps) is (velocity of sound in air = 360 m/s)
[KCET 1999]
Options:
A) 420
B) 360
C) 400
D) 320
Show Answer
Answer:
Correct Answer: D
Solution:
$ n’=n( \frac{v+v _{O}}{v-v _{S}} )n\Rightarrow 400=n( \frac{360+40}{360-40} )\Rightarrow n=320cps $
BETA
