What happens when a tea kettle whistles?

Here's how it works:

* Steam Formation: As the water heats up, it turns into steam, which is water vapor.

* Pressure Buildup: The steam has nowhere to go except up the spout, where it builds up pressure.

* Whistle Mechanism: The whistle is designed with a small chamber that has a small opening. The steam pushes against this opening, causing it to vibrate and produce the whistling sound.

The whistle acts as a warning signal, letting you know that the water is boiling and ready for use.