Question

what should be the dimensions and the shape of classroom so that no echo can be produced ?

Answer 1

From my point of view the classroom should be 17.2 m away from the sound producers .It can be rectangle, square,circle or any other shape.

Answer 2

1) THE DISTANCE BETWEEN THE OPPOSITE WALLS OF THE CLASSROOM SHOULD BE LESS THAN 17.2m SO NO ECHO IS HEARD.

2) THERE SHOULD BE NO DOME SHAPED STRUCTURE AS IT PRODUCES REVERBERATION AND MULTIPLE SOUNDS.

3) BENCHES IN THE CLASSROOMS ARE ALSO OF SOUND ABSORBING MATERIALS AND PREVENT ECHO OF SOUND.