1. The problem statement, all variables and given/known data An infinte cylinder (radius a) with a uniform volume charge density rho_v is given. The axis of the cylinder coincides with the z axis. The following magnetic field exists: B=B0cos(wt+a) for r<=a (i.e., inside the cylinder and on its walls) B=0 for r>a (i.e., outside the cylinder) One asks: 1) What is the magnetic vector potential everywhere 2) What is the electric field everywhere 3) What can one learn from the magnetic field boundary conditions 3. The attempt at a solution Unfortunately, I do not have any clue how to address this question. There is a static charge which generated a static electric field, and there is an induced electric field due to the alternating magnetic field. Is the overall electric field a superposition of the two electric fields or am I mistaken ? Do the boundary conditions imply that the cylinder behaves as an ideal solenoid ? Do I only need to find the rotor of the magnetic field to get the magnetic vector potential ? Thank you for the help !!!