AN UPPER LIMIT TO THE ELECTRODYNAMIC POWER OUTPUT FROM A THIN ACCRETION DISK AROUND A BLACK-HOLE

We examine the electrodynamic power output from a thin accretion disk surrounding a Kerr black hole. We derive an upper limit for the total power. We find that this limit is only moderately sensitive to most of the relativistic correction factors. In fact, this limit is less sens itive to the change in the black hole spin than one would expect from the change in the inner radius of the accretion disk. The disk around a rapidly rotating black hole will produce more nonthermal radiation t han a similar disk around a slowly rotating black hole of identical ma ss, but the difference is only a factor of approximately 1.7.