Question

when you shout inside an empty hall,you hear your own sound after a short time why does it happens?

Answer 1

Echo,

When you shout, you set out a cascade effect where particles start to vibrate and propagate the sound. When it reaches a wall the sound bonds back and travels back to your ears. This phenomenon is termed as echo.

Hope this helps!!! :)

Answer 2

Explanation:

When you shout in a vacant room the sound waves travel and hits the walls of the room and is reflected back to the ear. This is called eco and this process is taken only few seconds. You can find some differences between the original sound and the eco sounds, but the eco sounds are understandable and you can easily identify the sound.