Chapter 28, Problem 63P

A circular loop of wire having a radius of 8.0 cm carries a current of 0.20 A. A vector of unit length and parallel to the dipole moment if the loop is given by (This unit vector gives the orientation of the magnetic dipole moment vector). If the loop is located in a uniform magnetic field given by find (a) the torque on the loop (in unit-vector notation) and (b) the orientation energy of the loop.