The plane of a rectangular coil, 4 cm by 6 cm, isperpendicular to the direction of a magnetic field B. If the coilhas 75 turns and a total resistance of 9 , at what rate mustthe magnitude of B change to induce a current of 3 A in thewindings of the coil? The plane of a rectangular coil, 4 cm by 6 cm, isperpendicular to the direction of a magnetic field B. If the coilhas 75 turns and a total resistance of 9 , at what rate mustthe magnitude of B change to induce a current of 3 A in thewindings of the coil?
Explanation / Answer
Giventhat the area of the rectangle is A = 0.04*0.06 m2 = 24*10-4 m2 Numberof turns is N = 75 turns Theresistance is R = 9 Thecurrent is I = 3A ------------------------------------------------------------------------------------------- The induced emf is = N*d /dt I*R= N*d /dt I*R= N*A*dB /dt dB/dt = I*R / N*A = ------------ T/s Numberof turns is N = 75 turns Theresistance is R = 9 Thecurrent is I = 3A ------------------------------------------------------------------------------------------- The induced emf is = N*d /dt I*R= N*d /dt I*R= N*A*dB /dt dB/dt = I*R / N*A = ------------ T/s