a girl uses a jump rope made of flexible wire. she holds the ends of the rope in extended hands, so the rope had approximately the shape of a semicircle of radius 0.850 m and she whirls the rope at a rate of 1.00 revolution per second at a place where the magnetic field of the earth is nearly vertical, of magnitude 5.00 x 10^-5 T. The motion of the wire rope generates an alternating emf between the ends of the rope. What is the amplitude of oscillation of this alternating emf?