We consider a cylindrical metallic magnet that is set into rotation about ahorizontal axis by a falling mass. In such a system the magnetic field willcause a radial current which is non-solenoidal. This leads to chargeaccumulation and a partial attenuation of radial current. The magnetic fieldacting on the radially flowing current slows down the acceleration. Usingnewtonian dynamics we evaluate the angular velocity and displacement. Weexplicitly show that the electromagnetic angular momentum must be taken intoconsideration in order to account for the change in angular momentum due to theexternal torque on the system. Further the loss in potential energy of thefalling mass can be accounted for only after taking into consideration theelectrostatic energy and the Joule loss. We suggest that this example will beof pedagogical value to intermediate physics students. A version of this isscheduled to appear in American Journal of Physics 2011. Keywords: Rotating magnet, Charge accumulation
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