Question

1. A 560-turn coil with diameter 80 mm sits above the lecture table as shown. A permanent magnet 0.70 T North pole slides underneath the coil in 0.50 s. a) what direction is the final magnetic field? b) draw the direction of the induced electric field in the wire c) calculate the average induced emf in the coil O

Answer 1

Sol D = 11 Somm 8 cm N=560 E B = 0.70T O, SOS s 3 N will So (a) cohen North pole Crossing the coil last at South - pole Cross the loop it has to oppose the change in flux So it has to develop the Norths-pole magnetic field points from the • Northpole North pole to South - pole Hence direction of magnetic field towards upwards. (b) Direction of is such it should oppose Change in magnetic flux Cao). So Current has to flow Antia clock wire direction. direction of induced emf which Current also shown adjacent figure. B N induced enf a way that the in So drives the ay (C) Know induced average E enf in the Coil 11 udda dt E 560 (BA) . too's E 11 560 X 0.70 * 3.14 x(8x16232 14 X 0.5 3.94 x604x164 3.94 v .: Induced eonf average value E = 3.94 V 3. 941