Like if I have a really bright flashlight I can feel heat from the beam, but I can blast a speaker at max volume and I might even feel the vibrations in my hand, but there’s no change in temperature.
Is this a glitch in the matrix?
In: Physics
There are 3 factors here.
* The sound wave itself doesn’t add much energy. The individual molecules are already bouncing around at the speed of sound. The fact that a wave is moving through them doesn’t change their average velocity by an appreciable amount. (But in extreme cases it can. Look up [acoustic refrigeration](https://en.wikipedia.org/wiki/Thermoacoustic_heat_engine).)
* Sound isn’t just compression. It is also rarefaction (low pressure) between the high pressure peaks. The transfer of heat (ignoring radiation) is based on the number of collisions between air and the object. While the high pressure regions have more collisions the low pressure regions will have less. This averages away much of the effect that you might expect.
* If you can feel the vibrations then it is producing heat in your hand. (Any time something deforms there will be heat generated.) However it is an extremely small amount of heat and is too small to notice.
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