A very long, straight solenoid with a cross-sectional area of 2.02 cm2 is wound
ID: 1411735 • Letter: A
Question
A very long, straight solenoid with a cross-sectional area of 2.02 cm2 is wound with 91.3 turns of wire per centimeter. Starting at t = 0, the current in the solenoid is increasing according to i(t)= ( 0.163 A/s2 )t2. A secondary winding of 5turns encircles the solenoid at its center, such that the secondary winding has the same cross-sectional area as the solenoid.
Part A
What is the magnitude of the emf induced in the secondary winding at the instant that the current in the solenoid is 3.2 A ?
Express your answer with the appropriate units.
|E| =
Explanation / Answer
As, magnetic field = uo * N * I
=> magnetic flux = n * uo * N * I * A
=> emf induced = n * uo * N * dI/dt * A
= 5 * (4 * 3.14 * 10-7) * 9130 * (0.163 * 2 * 4.43) * (2.02 * 10-4)
= 1.672 * 10-5 V