Please, let me know how pitch and vibration affect sound?

Question:

Please, let me know how pitch and vibration affect sound?

its my son project!!!

Best Answer - Chosen by Asker: The size & kind of the material vibrating helps determine the frequency of the vibration, which determines the pitch* of the sound.

*pitch:
the property of sound that varies with variation in the frequency of vibration
(from Wikipedia)
http://onelook.com/?w=pitch&ls=a...
http://watchtower.org/e/20000601/article...