RL Circuit Decay After Source Removal

An RL circuit begins to decay after the DC source is removed. At that moment, the circuit becomes source-free. If the inductor has an initial current, I0, it also stores initial energy. That stored energy drives the natural response of the circuit.

Kirchhoff’s voltage law is applied around the lo...

When a DC source is suddenly disconnected from an RL circuit, it becomes source-free.

Assuming the inductor has an initial current i₀, the initial energy stored in the inductor can be determined.

Applying Kirchhoff's voltage law around the loop and substituting the voltages across the inductor and resis...