It produces a sensation which is called sound.
When a stone is dropped into the water, what does it produce?
It produces waves in the water.
How do these waves move?
They move in every direction from the stone.
Do they get smaller the farther they go?
They do get smaller and smaller, until at last they disappear.
Do the waves of sound in the air act in the same way as the waves in the water?
They do act in the same way.
What then becomes of the waves of sound?