Answer:
The time constant τ = L/R represent the time requiered for the curent to get value of 63 % of its maximun value
Step-by-step explanation:
In a circuit RL ( serie circuit with a resistor R and the inductor L ) when a voltage is applied the inductor will have a reaction, such reaction consist in the creation of an electromotive force which will prevent the current to get its maximun value. The time constant which in the case of an inductor is
τ = L/R , represent the time requiered for the crrent to be 63 % of its final value