A metal rod PQ moves with a velocity v parallal to a very long straight wire CD carrying a current I as shown in Fig. 25.15. The ends P and Q of the rod are at distances a and b from the wire as shown. Obtain the expression for the emf induced between the ends of the rod. b a -D I Fig. 25.15

5. A 25.0 cm long solenoid has a radius of 3.00 cm and has 2000 turns of wire. The current in the solenoid varies according to the function I (t) = 6t - 8t2, where I is in amperes and t is in seconds; the direction of the current in the solenoid is shown below (clockwise as seen from the left). A copper ring of radius 5.00 cm and resistance 0.200 is placed around the solenoid. What is the magnitude and direction (specify clockwise or counterclockwise) of the current in the copper ring at t = 0.500 s? Isol

Answer c

A segment of wire 7.4 cm long is moving at a velocity of 7.08 m/s toward a parallel (much longer) wire which carries a current of 7.55 A. At a particular instant the wire segment is 5.4 cm away from the long, current-carrying wire. What is the induced emf (voltage) between the two ends of the wire segment?     1.47E-05 V     5.88E-06 V     1.18E-05 V     1.91E-05 V