Question

Solution to Practice Test Problem 7.10(Simple RL Decay Problem) Problem: A 0.02H inductor carries a current of 3A at time t = 0. The inductor discharges through a 312 resistor. Compute the time it takes the current to decay to 1A. Select One of the Following: (a) 0.0027s (b) 0.06 (c-Answer) 0.00738 (d) 0.00675 Solution For a discharging RL circuit, 1A = 3Ae- Total Points for Problem: 3 Points

Answer 1

For RL circuit, current in the circult, discharging atly I = Io e Here Io is the current at tzo T is the time constant, Y= L/R Herce, Io = 3A R = 3.1, L= 0.02 H Now set at t seconds. I = 1A.

ai from ean o we get -t/1R) 1-32 Se, time taken to -te e 1/3 -tx3 decay the current 2 e 13 to i A 0.0073 tx3 - luz t 0.02xluz 3 2 0.0073S