A circuit consists of a 9.3-mH coil,a 16.0-V battery,a parallel combination of a 19-Ω resistor and a 6.0-Ω resistor,and a switch,all in series.What is the time constant of this circuit?
A)3.7E-4 s
B)2.0E-3 s
C)4.9E-4 s
D)3.3E-2 s
E)This circuit has 2 time constants.

Question

Quizplus · Accepted Answer

The time constant (τ) for an RL circuit is given by τ = L/R_eq, where L is the inductance and R_eq is the equivalent resistance of the resistors in series. The equivalent resistance of the parallel resistors is 1/R_eq = 1/19 + 1/6, which gives R_eq = 4.5 Ω. Thus, τ = 9.3E-3 H / 4.5 Ω = 2.0E-3 s.

A Circuit Consists of a 9