Chapter 20, Problem 22P

An N-turn circular wire coil of radius r lies in the xy-plane (the plane of the page), as in Figure P20.10. A uniform magnetic field is turned on, increasing steadily from 0 to B₀ in the positive z-direction in t seconds. (a) Find a symbolic expression for the emf, ε, induced in the coil in terms of the variables given. (b) looking down on at the xy-plane from the positive z-axis, is the direction of the induced current clockwise or counterclockwise? (c) If each loop has resistance R, find an expression for the magnitude of the induced current, I.