What is the difference between electromagnetic radiation and an electromagnetic field?

1 Answer
Dec 7, 2016

This is a very good question indeed...albeit...quite difficult! I'll try....

Explanation:

Electromagnetic field is the disturbance of space around a charged particle moving into it.

Imagine a charged particle (an electron, for example) travelling through space with a certain velocity (figure (a) below). Around it the space is perturbed because of its presence; you can see this if you put a second charge in it; the new charge will "feel" the first one (the field produced by it).

Now let us go back to our initial charge; try to accelerate it (figure (b) to (e)).
This acceleration will produce a ripple into that initial field, exactly as a wave in a pond, that will propagate through space and that we call electromagnetic radiation.

Ohanian Physicse

The interesting thing is that em radiation will propagate because of the presence of the em field so they are both closely connected!!!