Question

Why does the sound of the bell Slow down the air
is sucked through the glass?​

Answer 1

Sound needs a medium to travel.

The vacuum pump pumps out the air, and thus the medium through which the sound travels is pumped out.

So, the sounds gets fainter.

Answer 2

The sound of the bell slows down due to the absence of medium.

• In the bell experiment when air is sucked through the glass, it creates a vacuum in the glass.
• We very well know that sound cannot travel in vacuum, it needs a medium to travel.
• Hence as the air is sucked out the sound of the bell also decreases as the medium in which sound travels has decreased.