a person standing 100m away from a wall fires a gun and hears and echo. Calculate time after which an echo is heard.
a. 1.02 sec
b. 0.42 sec
c. 2.05 sec
d. 0.61 sec​

Respuesta :

Answer:

Time for sound  to travel to wall and back

T = S / V = 200 m / (331 m/s) = .60 sec

d) is correct