system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Is it possible to heat up an object by playing a loud enough sound? If so how loud would it need to be?

[first post in reddit] Going on the basis that sound is a wave of vibrating particles and when particles vibrate they heat up. Could you get the object to vibrate enough due to the sound to heat up? How loud would this object then need to be?
gpt
It's not a matter of volume (amplitude), or frequency really, it's "total sound energy". Higher frequencies can deliver more sound energy at a given volume, so the choice to be louder or higher-of-pitch depends on the immediate goal (e.g. what exactly you are trying to heat).

So there are lots of "ultrasound" medical devices and some are designed specifically to deliver heat to deep tissue.

And "ultrasonic humidifiers" add _heat_ to water without raising its temperature in order to create that "cold mist". This one is particularly tricky to understand since most people think heat and temperature are the same thing.

So the truth is that _all_ sound delivers _some_ heat energy to everything it touches. How much is delivered and over what area is a whole bunch of math.

There are some good articles and youtube movies available if you google "sonic heating" and "Thermoacoustic".