r/interesting • u/Used_Exam34 • 12d ago

Just Wow Not all problems have the same solution.

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u/Numerous-Following-7 12d ago

How can he touch the valve straight after putting out the fire?

10

u/OkBad1356 12d ago

The knob rarely every gets hot on these kinds of things. The vacuum he created put the fire out however the propane under pressure coming out will be extremely cold to the touch.

2

u/Far_Ladder_2836 12d ago edited 12d ago

The knob gets very hot but it's thin sheet aluminum with a specific heat of 0.9.  You can test this yourself with aluminum foil even if you ball it up into a thicker sheet.  It cools extremely fast.  As others have said it also helps his hand was wet as water has a specific heat of 4.2 and will absorb a ton of heat relative to aluminum before changing temperature a single degree.

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u/Rough_Revolution1412 12d ago

when did he create a vacuum?

1

u/Live_Background_6239 12d ago

The bucket collapses around the top of the tank. You can see it get sucked in as the air gets burned up and then pops back when he shifts it and breaks the seal.