Chapter 27, Problem 27.71P

The loop of wire shown in Fig. P27.71 forms a right triangle and carries a current I = 5.00 A in the direction shown. The loop is in a uniform magnetic field that has magnitude B = 3.00 T and the same direction as the current in side PQ of the loop, (a) Find the force exerted by the magnetic field on each side of the triangle. If the force is not zero, specify its direction, (b) What is the net force on the loop? (c) The loop is pivoted about an axis that lies along side PR. Use the forces calculated in part (a) to calculate the torque on each side of the loop (see Problem 27.70). (d) What is the magnitude of the net torque on the loop? Calculate the net torque from the torques calculated in part (c) and also from Eq. (27.28). Do these two results agree? (c) Is the net torque directed to rotate point Q into the plane of the figure or out of the plane of the figure?

Figure P27.71