11. A small sphere of mass m carries a total charge q. The sphere hangs from a silk thread between two large parallel conducting plates. The excess charge on each plate is equal in magnitude, but opposite in sign. If the thread makes an angle of e with the positive plate as shown, what is the magnitude of the charge density on each plate?

11. A small sphere of mass m carries a total charge q. The sphere hangs from a silk thread between two large parallel conducting plates. The excess charge on each plate is equal in magnitude, but opposite in sign. If the thread makes an angle of e with the positive plate as shown, what is the magnitude of the charge density on each plate?