Question

Three boys rahul, raju, and ravi stand at three places and clap their hands simultaneously. Calculate the time between the clap and the echo of the clap of each body. Infer how can the time between the clap and echo of the clap varied. Velocity of sound in air is ${330ms}^{-1}$.

Answer 1

If t be time between the clap and echo, then the total distance traveled by sound in each case in time t will be double the distance between reflecting surface and the each body.

Using $S=vt$,

for rahul: $t=S/v=\frac{2\times 50}{330}=0.3s$;

for raju: $t=\frac{2\times 75}{330}=0.45s$ and

for ravi: $t=\frac{2\times 100}{330}=0.61s$

Thus, time increases with the increase in distance.