Problem 3: Consider a pair of very very long straight wires carrying cur- rent I , separated by a distance 2 a, connected at their ends by a semicircular arc of wire of radius a as shown. What is the magnetic eld B at the point. indicated as Q? Give the magnitude and the direction of the eld. Unlike what is shown in the drawing, the idea is that the straight portions go on for a very long distance; way way longer than a. Hint: You will want to use superposition and symmetry to solve this one, not the integral