fig 29 56 four long straight wires are perpendicular page and their cross sections form squa
In Fig. 29 56, four long straight wires are perpendicular to the page, and their cross sections form a square of edge length a = 6.65 cm. Each wire carries 18.7 A, and all the currents are out of the page. What is the magnitude of the net magnetic force per unit length on wire 1?