Question

we cannot hear the echo produced in a classroom ​

Answer 1

Explanation:

The distance between two walls of a classroom is less than 17.2 m. Therefore the time taken for the echo to reach our ears is less than 0.1 s. Thus we are unable to distinguish between the original sound and the echo produced. Hence echo can't be heard in a classroom.

Answer 2

Answer:

We can still hear an echo in the classroom if it's is empty

Explanation:

But sometimes takes more time to hear echo