We all agree that a charge moving towards a stationary magnet will be acted on by a force, what about in the above case?
The force will be exactly the same, only changing v by -v in Lorentz formula, as if the electric charge were moving if you assume an inertial system. The only problem that you have is that the magnet produces a non radial magnetic field if the poles are closed and therefore the things would be very symmetric "electricity"-"magnetism" if you could choose a very long magnet.
The explanation is that you can exchange rest observers on the magnet with respect to electric charge or vice verse using Lorentz transformations assuming inertial observers. If the system is not inertial the things are much more complexes to say.
I just subscribe to Daniel's answer:
Make your life easier by passing to a frame of coordinates in which the magnet is static and the charge moves. If the movement is not at constant speed, then divide the time into very short intervals in which the velocity can be considered constant.
In the new frame calculate the electric and magnetic field. The electric field is produced by the charge, and the magnetic field is produced by both the current generated by the moving charge, and by the magnet.
After calculating these two fields, apply the Lorentz transformation back to the frame in which the magnet is at rest. The Lorentz transformation of the e.m. field will give you the two fields in the old frame. So, you will find the magnetic force that act on the magnet and the electric force on it (if there is such a one).
- Badges
- Science topic
- Similar topics
- Engineering
- Electrical Engineering