The sound produced in a big hall repeats itself. Why ?

Sound is produced by

Why is the sound produced in air not heard by a person deep inside the water ?

why do we hear the sound produced by the humming bees while the sound of vibrations of pendulum is not heard ?

why do we hear the sound produced by the humming bees while the sound of vibrations of pendulum is not heard ?

Sound is produced by _____.

Why a given sound is louder in a hall than in the open?

Name the following. A motion that repeats itself at regular intervals

A person deep inside water cannot hear sound produced in air. Why?