When you do something that makes a sound, why does it produce noise?

Question

For example when you crumple a piece of paper, why does it make that crunching noise? Why the the paper not simply fall into itself?

In: Physics

Answer 1

Sound is just your brain’s interpretation of vibrations in the air, picked up by the ears. If something makes vibrations in the air at a frequency and sufficient intensity that can be picked up by our ears, it is interpreted by your brain as sound. Crumpling paper causes pressure changes (vibrations) in the air that fit those frequency/intensity requirements to be picked up and interpreted as sound.