1. The problem statement, all variables and given/known data You have a coil of N turns, with current I through it. It is in a magnetic field B, which causes it to feel a torque. Give an expression for its magnetic dipole moment. 2. Relevant equations 3. The attempt at a solution Well, I know magnetic dipole moment is A x I So for a coil of N turns it should be A x IN. The problem is, A isn't specified in the problem, which makes me wonder if there's a better/different way to do this. Any ideas?