Question

An electric bell is kept under a bell jar in which a vacuum has been created. Slowly air is introduced in to the jar. What will happen to the sound of the electric bell?Select one of the options below as your answer:
A. It will increase until it reaches its maximum.
B. It will decrease until it stops.
C. It will not change.
D. It will increase and decrease periodically
.E. It will decrease exponentially

Answer 1

http://www.youtube.com/watch?v=ce7AMJdq0Gw

Answer 2

A. It will increase until it reaches its maximum.

Answer 3

sound can not travel through vacuum

Answer 4

As the air is introduced into the bell jar, the air vibrates to produce sound. So eventually the sound will increase to maximum.
:D