Question

we cannot hear the Echo produced in a classroom .give scientific reason.

Answer 1

Echo is a sound produced when the original sound is reflected by walls of a given room. For in stance in a small room If there is hard walls there will be an echo of sound bouncing off the wall but because the sound bouncing is so close to the original, it is harder to detect the echo produced. In room having curtains, carpets, soft sofas no echo is detected since the sound is absorbed.

So for the case of a classroom, no echo is produced because the learners and the furniture block the sound from reaching the wall hence no bouncing back of sound.

Answer 2

Echo min. distance to be heard is 17.2 m