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Physics 106b – 2014 Assignment 7 Due: Friday, March 28 at 4:00 pm Reading: 27.1-27.3, 27.6 Assigned exercises: Mastering Physics assignment 7 Individual problems: 27.45 (You should do 27.44 first) Group problems: 26.61 27.42 27.44 7A. Identify three regions in the figure to the right where there must be current flowing. Explain your reasoning, and state which direction the current must be flowing in each region. 7B. A rectangular mathematical loop lies in the plane of the page. Its width (in the x-direction) is 7.00 cm, while its height (in the y-direction) is 4.00 cm. The bottom arm of the loop is at y = 5.00 cm, so that the top arm is at y = 9.00 cm. The left arm is at x = 1.00 cm, so that the right arm is at x = 8.00 cm. The magnetic field in this region is given by B=( 100 μ T/m) y ^ i . How much current threads through the loop, and it what direction does it flow? (Assume any electric fields present are constant in time.) 7C. A conducting slab extends infinitely in the x and y directions and has thickness h in the z direction. It carries a uniform current density (i.e. current per cross-sectional area, having units of A/m 2 ) J flowing in the positive x direction. Find the magnetic field (direction and strength) a) inside and b) outside the slab, as functions of the distance z from the center plane of the slab.
