College Physics 10th Edition by Raymond Serway,Chris Vuille

Exercise 44

A circular coil enclosing an area of 100 cm 2 is made of 200 turns of copper wire. The wire making up the coil has resistance of 5.0 V, and the ends of the wire are connected to form a closed circuit. Initially, a 1.1-T uniform magnetic field points perpendicularly upward through the plane of the coil. The direction of the field then reverses so that the final magnetic field has a magnitude of 1.1 T and points downward through the coil. If the time required for the field to reverse directions is 0.10 s, what is the average current in the coil during that time