일반물리학 2 — Magnetic Fields: Problem 19

19 Figure 28-29 shows a rectangular 28-turn coil of wire, of dimensions 10 cm by 5.0 cm. It carries a current of 0.80 A and is hinged along one long side. It is mounted in the $xy$ plane, at angle $\theta = 25^\circ$ to the direction of a uniform magnetic field of magnitude 0.50 T. In unit-vector notation, what is the torque acting on the coil about the hinge line?