I'm do the efforts to create a fantasy scifi story around magic being just another kind of energy. It would certainly be favor electricity but with a few quirks. Ns am going to basic the "power limit" (basically how much magic a person would have the ability to safely manipulate) on exactly how much energy is required to kill a person via 1.) Electricty 2.) warmth 3.) Ionizing(?) Radiation 4.) plain old dull force

Electricity:

Generally a existing through the heart between 100 and 200 mA is taken into consideration directly lethal through very little chance of survival. Keep in mind that higher current in reality raises the possibility of survival together the muscular mouse inhibits the love from going right into ventricular fibrillation.

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Now, skin has actually a facility voltage-current-resistance relationship, yet if we consider a macroshock of about 220 V
50 Hz applied on relatively large areas (i.e. Ex. Palms, or palm and sole) of wet skin top top two significant limbs, wherein there is no forced penetration of skin, one impedance of about 1400 Ohms is reasonable.

That provides us ~150 mA, best in the deadly range. That gives ~34.5 W, therefore ~34.5 J/s. One 2nd of exposure is most more than likely lethal. If applied directly come the heart, a lot much less is necessary to kill.

This formulation doesn't feel fairly right for r/AskScienceDiscussion yet the inquiry is fun and also I have actually time to be procrastinating. If extremely trained wizards have actually very specific control over the application of magic climate killing a human doesn't take it much:

Disclaimer: math has actually been half-assed

If friend boiled the medulla oblongata, mine guess is around 50 grams the tissue, heated come 100 oC indigenous 37 oC, or 50x63x4.184 = 13,179 Joules.

This is the approach I like, yet if OP really wants to cheap out on energy use they could get away with heating 1 g that medulla indigenous 37 to 60°C, around 84 J (estimating brain specific heat capacity 3.65 J/gC).