Question

What is the minimus time for sound to create an echo?​

Answer 1

So the most important condition for hearing an echo is that only after a lapse of at least 0.1 seconds after the original sound dies off, should the reflected sound reach the ear. Since the sound speed is 340 m / s the sound traveling distance is 34 m in 0.1 second.

Answer 2

Answer:

0.1s

Explanation:

The echo must be heard 0.1s after the original sound to be able to distinguish between the two.