Three LR circuits are made with the same resistor but differ

Three LR circuits are made with the same resistor but different inductors. The figure shows the current of the circuits as a function of time. Show on the time scale the approximate locations of tau of each plot. Rank the three inductors according to the value of inductance, L.

Solution

Order:L3>L2>L1

Explanation: I=io×e^(-t/LR)

As L increases I decreases rapidly