What is an echo?
Sound waves may be meditated off any moderately flat floor like a cliff, excessive wall or mountain. When this floor is neither too close to nor too far, a legitimate made via way of means of you hits the floor and springs lower back to you as an echo. The similarly the floor is from you, the weaker the echo and the longer it's going to take for the echo to return. The waves keep bouncing returned and forth, getting weaker as they travel, till they lose power and die out.
