wave_mechanics dopplers_effect Question 59
Question: When an engine passes near to a stationary observer then its apparent frequencies occurs in the ratio 5/3. If the velocity of engine is
[MP PMT 2003]
Options:
A) 540 m/s
B) 270 m/s
C) 85 m/s
D) 52.5 m/s
Show Answer
Answer:
Correct Answer: C
Solution:
When engine approaches towards observer $ n’=n( \frac{v}{v-v _{s}} ) $ when engine going away from observer $ {n}’’=( \frac{v}{v+v _{S}} )n $
$ \therefore $
$ \frac{n’}{n’’}=\frac{v+v _{s}}{v-v _{s}}\Rightarrow \frac{5}{3}=\frac{340+v _{s}}{340-v _{s}}\Rightarrow v _{s}=85 $
$ m/s $ .
BETA
