The problem is that a space heater develops a short circuit when to much current enters the circuit. The power supplied is 1500 W and the max current before short circuit is 15A.(adsbygoogle = window.adsbygoogle || []).push({});

Firstly we have to calculate the resistance of the heater where I used P = I^2 R.

But now we have to find the max reistance of the short circuit using circuit analysis, which we know R of the heater from before but we don't know the total current supplied.

I read somewhere that the resistance of a short circuit is zero, but I may have read this wrong.

Then we have to find the mimimum diameter of the wire(the short circuit) if it s 3mm long. It also givees a temp os 273K, and at this temp the heater wasn't working.

Now I know you can set the derivative equal to zero to find max/min values. The other attempt I tried was to use alpha E = I/A, but after some algebra I get and area on both sides in the denominator, and they cancel, and I'm left with V/R = I.

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# Homework Help: Short Circuit

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