1. An infinite straight wire on the z-axis carries current I2=3.6A in the +z direction, upward. A rectangular loop is placed in the xz plane with its nearest side parallel to the wire a distance d=0.9m away. The loop has height (z-length) h=1.5m, width (x-length) w=1m, and carries a current I1=1.2. 2. Equations B = Iμ/2∏r F = Il X B F = I2(μI1/2∏d) 3. The attempt at a solution I tried using the equations, first by solving for B and plugging in μ, I1, and r=0.9 Then I used second equation and multipled I2 times that B, I got as an incorrect answer 9.6e-7 So i've drawn the diagram, but I'm missing where the height and length of the loop come into the equation, i'm certain they are part of the problem solving since I omitted them from my attempt. I also know the perpendicular-to-wire sides of the square loop cancel out, so I need to focus on the parallel parts?... FINAL EDIT: Ah now I know, I needed to use this: (I2h)(μ0I/2π(d)) - (I2h)(μ0I/2π(d+h)) My question now is why is the current of the infinite wire multiplied by the height of the square loop in this equation? Because the height is the length I assume? Just want to double check. And also why is it necessary to subtract one F from the other?