Playing sounds with only one frequency at a time

1. What do we call a sound that consists of only one frequency?
2. What happens if you play all frequencies at once?
3. How can we hear multiple frequencies at once?
4. Do you hear sounds around you as one frequency at a time or as many frequencies at once?

What do we call a sound that consists of only one frequency?

Sound consisting of a single frequency is called a tone. On the other hand, a note is usually made up of a number of frequencies. Pitch is a measure of how shrill a sound is.

What happens if you play all frequencies at once?

A speaker putting out every frequency at once is producing “white noise”, like an AM radio off frequency (the sound you're hearing is the sun).

How can we hear multiple frequencies at once?

The way that sound works is you can superimpose the motion of the speaker - meaning lots and lots of different vibrations - and that will produce sounds of lots and lots of different frequencies all at the same time, by just making the right pattern for the speaker to move back and forwards.

Do you hear sounds around you as one frequency at a time or as many frequencies at once?

The human ear doesn't hear one frequency at a time. A way to physically see what the ear is experiencing is to take a pool of water.