Echo

An echo occurs when sound waves travel through the air, hit a surface like a wall or mountain, and then bounce back to your ears. This bouncing creates the repeating sound we hear as an echo. The time delay between the original sound and the reflected sound depends on the distance to the surface. Echoes help animals and humans identify distances and shapes of distant objects. In technology, echoes are also important in systems like sonar and radar, where reflected sound or radio waves are used to detect and locate objects underwater or in the air.