Relative Motion and Electromagnetism
Most recent answer: 04/01/2014
- Philip (age 17)
Australia
Let me start with the second question.
Let's say that you look in a frame where a magnet is at rest and a wire is in motion at right angles to the magnetic field. Then there's a "Lorentz force" on the charges moving through the field, and that force causes the charges to move along the wire.
In the frame where the wire is at rest and the magnet is moving, the moving magnet makes an electric field. That field exerts a force that causes the charges to move.
So the description changes between the frames, but the basic physical effects remain the same. We know that some features of the physical situation are "invariant"- the same in eaach reference frame. Special Relativity amounts to making a consistent acount of what those features are.
As for what "relative motion" is, I can't think of anything to say except that it's the motion of one object as seen from the other's point of view.
Mike W.
(published on 04/01/2014)