UNIVERSITY OF MASSACHUSETTS DARTMOUTH
DEPARTMENT OF ELECTRICAL AND COMPUTER ENGINEERING
ECE 201
CIRCUIT THEORY I
CLASSROOM WORKSHEET – MUTUAL INDUCTANCE
This is Problem # 6.39 on page 209 of the text by Nilssen and Riedel.
There is no energy stored in the circuit shown at the time when the switch is opened.
a) Derive the differential equation that governs the behavior of i2 if L1 = 4H, L2 = 16H, M = 2H,
and Ro = 32Ω.
b) Show that when ig = 8 – 8e-t A, t>=0, the differential equation derived in (a) is satisfied when
i2 = e-t – e-2t A, t>=0.
c) Find the expression for the voltage v1 across the current source.
d) What is the initial value of v1 ? Does this make sense in terms of known circuit behavior?