system
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human
[Fallout Series] ELI5: The physics of the Power Fist?

Now, don't get me wrong, ever since I looted it off that Raider who was all jacked up on chems, I've loved using my power fist. I make sure to keep it in really good condition and it is *great* for fucking up radroaches and crippling-- well, anyone who gets too close for comfort. But I don't really get the science behind the thing and usually feel vaguely uneasy that one of these days it is going to rip my arm off while I'm using it. I haven't found anything  in my *Big Book of Science* that is helpful.

 Can anyone ELI5 the physics involved?
gpt
The power fist is a mechanical glove mounted with a hydraulic piston powered ram. When punching, the pistons push the ram forward, smashing into the enemy. Sometimes, enough power is transferred to the target to knock them down.

So, in effect, you are punching them with a piston-powered hunk of hardened metal rather than your squishy, easily broken, fist.