Two long concentric cylindrical conductors of radii a and b (b<a) are maintained at a potential difference V and carry equal and opposite currents I. An electron with a particular velocity 'u' parallel to the axis will travel un-deviated in the evacuated region between the conductors. Then u=?
The solution key contains the term for potential, this I can't understand because I had thought that when we having moving charges the electric fields transforms into magnetic fields. But here, the solution suggests that I should that I should account for both electric and magnetic fields.
In a similar post mine to mine, one of the users gave an answer that existence of moving charge and field charge together at same time is compatible, but how? How can you have free movement of charge to produce a magnetic field but at the same time some fixed charged which produces Electric field?