Here's why:

* Frequency refers to the number of sound wave cycles that pass a point in a given amount of time.

* Pitch is how high or low a sound appears to be.

The more cycles per second (measured in Hertz, Hz), the more frequent the sound waves are. Our ears perceive this as a higher pitch. For example:

* A low bass note has a lower frequency, meaning fewer waves per second.

* A high-pitched whistle has a higher frequency, meaning more waves per second.