what is the time constant of rl circuit
RL circuit These equations show that a series RL circuit has a time constant, usually denoted τ = L/R being the time it takes the voltage across the component to either fall (across the inductor) or rise (across the resistor) to within 1/e of its final value. That is, τ is the time it takes VL to reach V(1/e) and VR to reach V(1 − 1/e).