Magnetism was once thought to be distinct from electricity, but then Maxwell’s equations were found to describe both, and experiments connected them.
A static charge isn’t magnetic, but if it moves, a magnetic field appears around it. In Figure 5.12, passing a current I through the wire produces a magnetic field B, so wrapping a wire around a nail and passing a current through it makes it a magnet, and the effect stops when the current does. Electricity can then cause magnetism and the reverse is also true, as spinning a magnet with a wire wrapped around it induces a current in the wire.
Electric cars are then possible because in physics, magnetism and electricity behave as one field:
“We will see that magnetism and electricity are not independent things – that they should always be taken as one complete electromagnetic field.” (Feynman et al., 1977).
Is magnetism then just charge in another guise? (Note 1) It would seem not because:
1. Static charges and magnets don’t interact.
2. The magnetic field is at right angles to the electric field.
3. Gauss’s law doesn’t apply to magnetism, which reduces more like an inverse cube.
4. Dividing a charged body gives positive and negative charges but dividing a magnet gives two more magnets, both with a north and south pole.
Magnetism acts differently from charge, so how one field causes both is unclear. Light is also described as electrical and magnetic waves vibrating at right angles that cause each other, in a self-sustaining loop, which is illogical.
Current physics can explain electricity and magnetism separately, but not how they combine. It is as if we understood horses and birds, then found a winged horse we couldn’t explain. There is no credible theory that explains why electro-magnetism has different effects, that occur in different directions, and weaken differently.
The standard model explanation is that charges repel because virtual photons push them apart, but they also make charges attract and move magnets, so fairies with photon wands would explain electro-magnetism just as well! For this model to do better, the same quantum field that explains gravity must also explain electrical and magnetic effects without untestable inventions.
Note 1. The logic is that a moving electron’s length is foreshortened by special relativity giving more negative electrons than positive protons in a given length of wire, so parallel wires with opposite currents attract, but this could be correlation not causation