LR Time Constant on an Oscilloscope

The RL time constant is displayed on an oscilloscope to show how the current and voltage in a circuit containing a resistor (R) and inductor (L) change over time when a step voltage is applied. The time constant (τ = L/R) indicates how quickly the current reaches a certain percentage of its final value. By observing the exponential rise and fall of current and voltage on the oscilloscope, one can understand the dynamic behavior of inductive circuits.