I have a question regarding the interactions of electromagnetic fields. Say you have two superconducting electromagnets A and B. The properties of the magnets are known such that you can tell precisely how quickly it takes each one to produce it's full strength magnetic field and how long it takes for that field to no longer be present at the magnet when it is turned off. They are connected by a non-conductive rod at opposite ends at a distance equal to (time it takes for the field to no longer be present)x(speed of light). A________B A magnetic field is induced in magnet A. A))))))))B Using a very precise computer, you shut off magnet A's field. For a very brief period of time there should be no field present directly at magnet A, but the field is still propagating through space. A__))))))B Now if I turn on magnet B at that moment, producing a field with opposite polarity, magnet B should be repelled by that field. A__))))((B ---> My question is, if magnet B is pushing off of the field magnet A produced. But that field is no longer present in magnet A itself. What prevents the rod they are attached too from moving in a single direction, as there wouldn't be an opposite force acting on magnet A to cancel it out?