A) 1440 Hz
B) 240 Hz
C) 1200 Hz
D) 960 Hz
Correct Answer: C
Solution :
From Dopplers effect, the perceived frequency\[(f)\]is given by \[f=\left( \frac{v-{{v}_{o}}}{v-{{v}_{s}}} \right)f\] where\[{{v}_{o}}\]is velocity of observer,\[{{v}_{s}}\]. of source, \[v\]of sound and\[f\]the original frequency. Given,\[{{v}_{o}}=0\] (stationary), \[v=300\text{ }m/s\] \[{{v}_{s}}=200m/s,\text{ }f=400Hz.\] \[\therefore \] \[f=\frac{300\times 400}{300-200}=\frac{300\times 400}{100}\] \[\Rightarrow \] \[f=1200\text{ }Hz\]You need to login to perform this action.
You will be redirected in
3 sec