A) \[10\,\,m/s\]
B) \[20\,\,m/s\]
C) \[30\,\,m/s\]
D) \[40\,\,m/s\]
Correct Answer: C
Solution :
If the speed of engine is v, the distance travelled by engine in 5 s will be 5v and hence the distance travelled by sound in reaching the hill and coming back to the moving driver \[=900+(900-5v)\] \[=1800-5v\] So, the time interval between original sound and its echo \[t=\frac{(1800-5v)}{330}=5\] \[\Rightarrow \] \[v=30\,\,m/s\]You need to login to perform this action.
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