You are evaluating the performance of a large

Chapter 29, Problem 29.66

(choose chapter or problem)

You are evaluating the performance of a large electromagnet. The magnetic field of the electromagnet is zero at t = 0 and increases as the current through the windings of the electromagnet is increased. You determine the magnetic field as a function of time by measuring the time dependence of the current induced in a small coil that you insert between the poles of the electromagnet, with the plane of the coil parallel to the pole faces as in Fig. 29.5. The coil has 4 turns, a radius of 0.800 cm, and a resistance of 0.250 . You measure the current i in the coil as a function of time t. Your results are shown in Fig. P29.66. Throughout your measurements, the current induced in the coil remains in the same direction. Calculate the magnetic field at the location of the coil for (a) t = 2.00 s, (b) t = 5.00 s, and (c) t = 6.00 s.