# Is it possible to heat plasma to the point where there is no electrical resistance?

I was discussing Ohm's Law with my teacher and asked about what would happen if the resistance of a circuit was zero, to which he replied that the wire would melt. This got me wondering about plasma/ionised gas and whether or not it would have zero/negative resistance.

• To be clear, a wire with zero resistance would not melt as resistance is required to produce heat. I am assuming the "zero resistance" comment was implying a short circuit (i.e., no resistance other than the intrinsic resistivity of the wire and power supply), in which case, yes the wire would have issues. It may not melt though, e.g., aluminum sublimes if super heated like this... – honeste_vivere Sep 23 '16 at 21:05

• @mikuszefski: for a zero resistance wire and an ideal voltage source you get an infinite current, so the power dissipated in the wire in $\infty^2\times 0$ and this is undefined. However the power dissipated $\rightarrow \infty$ as $R \rightarrow 0$, so the teacher is correct in this sense. Of course for a real voltage source you need to include the internal resistance of the PSU. In this case the power dissipated in the wire would go though through a maxium then go to zero as $R \rightarrow 0$. Again, this is tangential to the OP's question. – John Rennie Apr 10 '15 at 10:42