Answer:
τ = 0.00203 seconds
Step-by-step explanation:
The time constant τ in a R-L circuit is given by
τ = L/R
First we have to find out the equivalent resistance of the circuit.
Since there is a parallel combination of 19 Ω and 6.0 Ω resistor
Req = 19*6/19+6
Req = 4.56 Ω
Now we can find out the time constant
τ = L/R
τ = 0.0093/4.56
τ = 0.00203 seconds
Therefore, the time constant of this circuit is 0.00203 seconds.