A circular loop in the plane of the screen lies in a 0.67 T magnetic field pointing into the screen. If the loop's diameter changes from 21.0cm to 6.0 cm in 0.50 s, decide the following.
1. What is the direction of the induced current?
2. What is the magnitude of the average induced emf?
3. If the coil resistance is 2.5, what is the average induced current?