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A Problem 3: Discharging a capacitor in a magnetic field A parallel plate capacitor with plates of area A sepa- rated by a small distance d along the z axis generates a uniform electric field E E2 between the plates. A uniform magnetic field B = Bê is applied parallel to the plates. X (a) Find the total electromagnetic momentum in the space between the plates. (b) The capacitor is slowly discharged through a resistive wire connecting the plates along the z axis. The current in the wire experiences a magnetic force. Find the total impulse delivered by this force, and compare with the total momentum that you found in (a). (c) What if the magnetic field is turned off instead? Does the changing magnetic field produce a net force on the capacitor? In which direction? How much impulse does this force deliver? HINT: Consider the net force on a thin slice of the capacitor between x and x + Ax and show that it is proportional to an emf & that you can calculate using Faraday's law. Add up all the force on all the slices. 2