The echo
Author : Abel Carenas Velamazán
Echo is an acoustic phenomenon produced when a wave reflects off a surface and returns to its emitter .
An observer is 510 m . of a wall . Between the observer and the wall , and at an equal distance from both , a shot is fired . After how many seconds will the observer perceive :
a ) Direct sound .
b ) The echo
Sound speed 340 m / s .
Related Topics and Concepts : Movement , sound Real Life Context : Physics