I'm wondering what causes the force is that holds wires together when their is a current flowing through them, and how to calculate it for different currents. As an example, when I am hooking my car battery up and you touch the jumper cable to the battery to connect the terminals, it kinda "sticks" and takes a little extra force to pull off the electrode. Other examples I've heard but not experiences is that a high-voltage line shorted to ground through a person will not be easy to pull away to break the short - it will take a significant force or different (lower R) connection to ground before the person can be broken away from the wire. I would guess this force arises from either the magnetic field generated by the current through the wire, _or_ perhaps from a coulomb force/interaction that occurs when attempting to cause a short (the voltage immediately forming at the short is like a parallel plate capacitor where the plates are pulled towards each other because of the different voltage on each plate). What which one is it, and how could it be measured for a wire? I'm curious because, in a superconducting wire, I'm wondering if this force could be used to strengthen the wire if very high currents are applied through the wire.