wave_mechanics dopplers_effect Question 16
Question: A source of sound is travelling towards a stationary observer. The frequency of sound heard by the observer is of three times the original frequency. The velocity of sound is v m/sec. The speed of source will be
[MP PET 1991]
Options:
A) $ \frac{2}{3}v $
B) v
C) $ \frac{3}{2}v $
D) 3v
Show Answer
Answer:
Correct Answer: A
Solution:
$ {n}’=n( \frac{v}{v-v _{S}} ) $
Therefore $ \frac{n’}{n}=\frac{v}{v-v _{S}}\Rightarrow \frac{v}{v-v _{S}}=3\Rightarrow v _{s}=\frac{2v}{3} $
BETA
