Question

A source of sound is kept in a jar in a vacuum. Air is slowly introduced in to the jar. What happens to the sound coming out of the jar?
a. The loudness of the sound increases gradually.
b. The loudness of the source decreases gradually.
c.The sound remains unchanged
d. The pitch of the sound increases gradually.
e. The pitch of the sound decreases gradually

Answer 1

A is the answer

Answer 2

thank you! @arindameducationusc

Answer 3

No problem ;)