College Physics 10th Edition by Raymond Serway,Chris Vuille

Exercise 54

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 B 0 in the positive z -direction in t seconds. (a) Find a symbolic expression for the emf, e , 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.