A boy receives the echo of his clap reflected by a nearby hill 0.8s later. How far is he from the hill? [ speed of sound in air = \(340ms^{-1}\)
A
528m
B
66m
C
136m
D
264m
Verified Correct Answer: C.
Physical Principles & Numerical Solution
Time for echo both ways = 0.8
Therefore time for echo in 1 way = 0.8/2 = 0.4
Distance = Speed x time
Distance = 340 x 0.4
Distance = 136m
Source: Myschool Past Questions Archive (Record #26976)