Sounds Like Science Vol. 1
Have you ever wondered why voices get higher pitched when sped up and lower pitched when slowed down? If you’ve ever learned about sound waves and frequency, you already kind of know the answer.
When you play a sound, the length of the sound waves determines the pitch you hear. The vibrations of the sound will be faster for high pitch and slower for low pitch. Shorter sound waves caused by the vibrations correspond with higher pitch and longer waves correspond with lower pitch. In other words, more full waves or vibrations in a set time frame equates to a higher pitched sound because more full waves reach your ear.
So why does the pitch change when you speed it up or slow it down? It’s because whatever is playing that sound is now reading it at a different speed (a different frequency) and changing the number of waves that hit your ear in a set time frame. When you speed up a sound, you compress the waves, resulting in more sound waves in a set time. The frequency is now increased, and the pitch is higher as a result. Similarly, when you slow down a sound, you elongate the waves, stretching them out over a longer time frame. The frequency is decreased, and the resulting pitch is lower.
Now you know.