Question

How does electric field and magnetic field nullify each other in emw?

Answer 1

First, in the land of the physical we have electric charges, but not magnetic charges.

So magnetism is a result, or effect, not an original cause. The original cause of magnetism is current flow.

Flow implies time. The flow is a flow of charge.

Thus an electric charge is a time based phenomenon. Movement of the charge through space causes a magnetic field. (Even an electron’s magnetic field is likely due to an equivalent current flow within the electron’s space, but that is just conjecture.)
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