I have included a picture. Question: What is the force on each wire if B = 1.656T, i = 10A, L1 = 7cm and L2 = 14cm? Now, I have checked my physics book, and the equation I have found is F_12 = mu_0*L*I1*I2/(2*pi*D) where D is the distance between the two wires, and L is the length of one wire. However, I tried that formula in the computer, and it doesn't work. I let L =L2 (m), D=L1 (m), I have tried I1=10 and I2=+/- 10...but it didn't work. I'm thinking there is another round about way to do this, but I don't know what. CAn someone lend me a hand?