Sprinklypoo

Sprinklypoo t1_j5pzecj wrote

Reply to If I had two cups of water, one normal size and one as big as a swimming pool and stirred them both with proportionally sized spoons, would the larger pool of water keep spiraling longer than the smaller? by r3volc

Yes. Mostly because of momentum and friction.

Your small cup has a much higher friction at the edges in proportion to the momentum of the circling liquid.

You could of course balance this by stirring the swimming pool at a slower rate - but that wasn't part of your question...

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Sprinklypoo t1_j5punwl wrote

Reply to Why does hot air cool? by AspGuy25

Barring fans and other means of heat transfer, your answer is flow. Heat flows. The PCB is hot, and the room ambient air is probably around 70F. The casing is heated by the PCB but cooled by the ambient air as the heat flows outward.

This can actually be quite accurately modeled, but I'd probably want a better picture of your solid state system before attempting to do so.

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Sprinklypoo t1_j18nllj wrote

Reply to Why do we use phase change refrigerants? by samskiter

really simply because all of the heat is contained in that phase change.

For instance, water takes about 100 times the energy to change phase (steam or ice) as it does to raise or lower 1 degree. Refrigerants are similar. You can focus on a specific temperature and provide a fairly solid state process.

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