1. The problem statement, all variables and given/known data The 10-turn loop of wire shown in the figure lies in a horizontal plane, parallel to a uniform horizontal magnetic field, and carries a 2.0A current. The loop is free to rotate about a nonmagnetic axle through the center. A 50g mass hangs from one edge of the loop. 2. Relevant equations Torque = r x F Torque = IA x B 3. The attempt at a solution My thought was to simply calculate the torque created by the mass and then relate that with an opposite torque provided by the magnetic field. I suspect that I'm calculating the torque created by the hanging mass wrong, since I haven't really dealt with torques in some time. Torque = r x F -> .025m*.05kg*9.8m/s^2 = .01225 Nm Torque = IA x B -> Torque/IA = B -> .01225/(2.0A*(.05*.1)) = B = 1.225 T If someone could help with what I'm overlooking here I would appreciate it.