I'm trying to write a fantasy scifi story around magic being just another develop of energy. It would certainly be prefer power but via a few quirks. I am going to base the "power limit" (basically how a lot magic a perboy would certainly have the ability to safely manipulate) on exactly how a lot power is compelled to kill a human through 1.) Electricty 2.) Heat 3.) Ionizing(?) Radiation 4.) Level old blunt force


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Electricity:

Generally a current with the heart in between 100 and 200 mA is thought about directly lethal with extremely little bit possibility of survival. Note that higher existing actually raises the opportunity of survival as the muscular cramps inhibits the heart from going right into ventricular fibrillation.

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Now, skin has actually a complicated voltage-current-resistance partnership, but if we think about a macroshock of around 220 V
50 Hz used on relatively big areas (i.e. ex. palms, or palm and sole) of wet skin on two significant limbs, where tright here is no compelled penetration of skin, an impedance of about 1400 Ohms is reasonable.

That gives us ~150 mA, right in the deadly selection. That offers ~34.5 W, so ~34.5 J/s. One second of expocertain is most probably lethal. If applied directly to the heart, a lot much less is needed to kill.


This formulation doesn't feel rather right for r/AskScienceDiscussion however the question is fun and I have actually time am procrastinating. If highly trained wizards have actually incredibly exact manage over the application of magic then killing a person doesn't take much:

Disclaimer: math has been half-assed


If you boiled the medulla oblongata, my guess is around 50 grams of tworry, heated to 100 oC from 37 oC, or 50x63x4.184 = 13,179 Joules.


This is the technique I prefer, yet if OP really wants to cheap out on power use they might obtain amethod via heating 1 g of medulla from 37 to 60°C, around 84 J (estimating brain specific warmth capacity 3.65 J/gC).


ionizing radiation

There's an extensive distinction between the power essential for dead ultimately, dead soon, and dead ideal there.

The dose for "instant and also long-term incapacitation" is about 8,000 rads. This was necessary knowledge for Cold War neutron tools. It's additionally a high estimate - 400 rads will certainly more than likely kill you eventually, however not without a weeks-lengthy "walking ghost" phase where you can still walk around and also carry out things while lack of cell department and a damaged immune system progressively catch as much as you. 8,000 is the dose wbelow your nervous mechanism stops functioning appropriately and also you most likely never before gain up aobtain.

Rads are an took in dose of 0.01 J/kg of ionizing radiation so for a 100 kg adult that's about 8000 J. A 5.56 55 gr from a lengthy barrel is about 1,300 J.

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Air will certainly absorb half the radiation eextremely few hundred meters depfinishing a small on kind so it's not really a sniper weapon. You also don't want also a tiny amount backscattering off the tarobtain and also onto you or they're dead ideal there and also you're dead ultimately.