# How is the loop law applicable when I connect a battery with an ideal copper wire?

We would have a potential rise but where is potential drop? Considering wire to be having negligible resistance.

• Possible duplicates: physics.stackexchange.com/q/8675/2451 , physics.stackexchange.com/q/80400/2451 and links therein. – Qmechanic Jun 15 '17 at 14:38
• not answered there!! – Kavya Negi Jun 15 '17 at 15:15
• your answer will be appreciated – Kavya Negi Jun 15 '17 at 15:15
• As I answered at physics.stackexchange.com/a/271068/73490 the ideal voltage source is analogous to an "unstoppable force" and the ideal wire is analogous to an "immovable object" and hence what you're asking is directly, "what happens when an unstoppable force collides with an immovable object"? If you don't add something which helps to resolve the paradox physically, then you will get an unphysical answer: an infinite current flows over the wire so that Ohm's law says $V = I\cdot R = \infty\cdot 0,$ which is an indeterminate form and can be thought to have a finite value. – CR Drost Jun 15 '17 at 16:24
• This leads me to a next question- what is the work of voltage in a wire/ – Kavya Negi Jun 15 '17 at 17:47

## 2 Answers

There would be a potential drop. If the wire has literally $0$ resistance, then this is a nonphysical question and no physical answer can be provided.

Energy will be lost due to heat in the wire. The current will will be very high, as $I=\frac{V}{R}$ and $R$ is very low, and the power dissipated (heat) will be very high, as $P=IV$.

A power source usually has internal resistance; if you short the terminals of your battery with a perfect conductor the internal resistance will limit the current (and the voltage drop across the internal resistance will equal the potential rise of the battery).

If you have a power source with zero nominal internal impedance (you can get really close with a good voltage regulator) the electronics behind this would still have a finite power - so when you short the terminals, the total amount of current that can flow will be limited by the construction of the power source.

And if you have a limitless power source, there are governments that will want to talk to you.