Disk of radius r and uniform surface charge density rotates with constant angular velocity what is the magnetic dipole moment.

Aball is rolled uphill a distance of 5 m before it slows, stops, and begins to roll back. the ball rolls downhill 9 m before coming to rest against a tree. what is the magnitude of the balls displacement? a. 4 meters b. 9 meters c. 14 meters d. 45 meters