A boy receives the echo of his clap reflected by a nearby hill 0.8s later. If the speed of sound in air is 340ms\(^-1\), how far is he from the hill?

JThomson

7 years ago

Let the distance between the boy and the hill be x
V=2x/t , where V is the velocity of sound in air and t is the time.
"2x" because the sound travels from the boy to the hill and then comes back as an echo.
V=340m/s, t=0.8s
340=2x/0.8
340×0.8=2x
272=2x
x=272/2
x=136m

Chikamiracle

7 years ago

please the calculation is wrong

how is the d speed is 3,400 not 3,.4 and the time change from 0.8 to 0.812 and that is not enough if...
3,400*0.812 =2,760.8m so the answeer is not there