Question

When you knock on a door, what causes you to hear a sound?

(A)Vibrations that cause sound beams
(B)Vibrations that cause sound waves
(C)Vibrations that cause sound circles
(D) Vibrations that cause sound signs

Answer 1

Answer:

Vibrations that cause sound waves.

Answer 2

Answer:

(C)

Explanation:

sound always travel in the form of waves.it is the characteristic property of sound.

when u knok on a door,vibrations are generated which causes sound waves