Arectangular loop of wire with sides 0.240 and 0.554 m lies in a plane perpendicular to a constant magnetic field (see part a of the drawing). the magnetic field has a magnitude of 0.579 t and is directed parallel to the normal of the loop's surface. in a time of 0.117 s, one-half of the loop is then folded back onto the other half, as indicated in part b of the drawing. determine the magnitude of the average emf induced in the loop.

Ametal ring 4.20 cm in diameter is placed between the north and south poles of large magnets with the plane of its area perpendicular to the magnetic field. these magnets produce an initial uniform field of 1.12 t between them but are gradually pulled apart, causing this field to remain uniform but decrease steadily at 0.240 t/s . (a) what is the magnitude of the electric field induced in the ring? (b) in which direction (clockwise or counterclockwise) does the current flow as viewed by someone on the south pole of the magnet?