According to Biot-Savart law, uniform motion (V
Where A is beta, many symbols here can't be typed, which is really difficult to explain clearly. If necessary, you can refer to the general physical electromagnetism part in the university, the magnetic field generated by moving charge, substitute the data into the formula to get the magnetic field at the corresponding position, and then calculate the magnetic field force according to the equivalent current value of point charge there. As far as magnetic field force is concerned, two charges attract each other.
Both of them are subjected to electromagnetic force, but considering that the electric field force is repulsive, which is much greater than the magnetic field force, the two-point charge should show the effect of electric repulsion.
If there are two wires with the same current, the power effect disappears, because the electric fields generated by the positive and negative charges in each wire cancel each other out, so the electrons moving in one wire are not affected by the power of the charge in the other wire, only magnetic force appears.
As for the critical state, I don't know what you mean.