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 ifs echo \[t=\frac{(1800-5v)}{330}=5\] \[\Rightarrow \] \[v=30\,m/s\]You need to login to perform this action.
You will be redirected in
3 sec