Self Assessment Quiz

1. A metal sphere of radius R has a charge Q and is uniformly magnetized with a magnetization .Calculate the angular momentum of the field about the centre of the sphere.

2. In Problem 1, if the magnetization of the sphere is gradually and uniformly reduced to zero (probably by heating the sphere through the Curie temperature), calculate the torque exerted by the induced electric field on the sphere and  show that the angular momentum is conserved in the process.