Mystery disk

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Can a disk defy the laws of physics and roll up an inclined plane instead of down? The mystery disk rolls uphill, but does not defy the laws of physics.

When applying Newton's second law to a situation, one must consider the sums of the forces AND the sum of the torques on a body. For the case of a disk on an inclined plane, if the force due to gravity is less than the frictional force, the disk will roll without slipping about the point of contact. The direction of the net torque about this point will determine which way the disk rolls. The movie compares a uniform disk to the mystery disk.

1. Where would the slug need to be for the mystery disk to roll downhill?
2. Where would the slug need to be for the mystery disk to remain stationary?
3. Describe the motion of the disk as the inclined plane is made steeper and steeper.