QP 31 A rectangular loop of wire is placed so that all but its bottom segment feels a uniform magnetic field Bo directed normal to the plane of the loop (see Fig. 1). The wire has a total mass M , resistance R, loop width w, and loop height h. The wire is allowed to fall under the inuence of Earth's gravity (acceleration = g). For this problem consider the loop only while the upper segment is still in the magnetic eld; also, ignore timevarying uxes arising from any induced currents. (i) G G) E} G G) G} FIG. 1: Starting position of the wire loop as it falls under the inuence of gravity. (3.) As the wire falls, in which direction will induced current flow in the loop (i.e., clockwise or counterclockwise in the gure above)? (b) At some particular time the loop has a downward velocity with magnitude '0. What is the current I owing in the loop in terms of v and other quantities specied above? [0) Suppose that the loop has fallen a distance 3; from the starting position shown in Fig. 1. Find the magnitude and direction of the magnetic forces acting on each of the four loop segments. Express your answers in terms of I and other quantities specied above. Indicate the directions of the forces in a sketch of the loop. ((1) If the loop's initial downward velocity equals a certain value ya, the total force (gravi tational and magnetic) on the loop vanishes for all y