Question

A ship which is stationary at a distance of 680 m from the shore, sends a signal to the coast. Its echo is heard in 4s. Find the velocity of sound.

Answer 1

d = 680 m
t = 4s
Sound takes 4s to travel to and from i.e., in 4s the distance travelled is 2 × 680 m.
∴ v = `(2"d")/"t"=(2xx680)/4` = 340 m/s.