I have a conceptual question, suppose we have a floating object (like a satellite), inside it we generate a beam of electrons that impact a positively charged metal plate, which produces an attractive force, this internal force will move the floating object? I was convinced that it was, but they told me that the net force on the closed satellite-electron system is zero (principle of action and reaction) Since the electron beam moves independently of the satellite and the positively charged plate (where the force is produced) is linked to the satellite, so I think this attractive force will move the satellite, am I correct?
The net force on the electrons+satellite system is indeed zero. But is the net force on the satellite alone (excluding electrons) zero? Since the electrons will be exerting a force on the satellite (by attracting the positive plate attached to it), the satellite does experience a non-zero net force, and hence, it does move.