7.1.1: Theory Overview

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The DC steady state response of RL and RC circuits are essential opposite of each other: that is, once steady state is reached, capacitors behave as open circuits while inductors behave as short circuits. In practicality, steady state is reached after five time constants. The time constant for an RC circuit is simply the effective capacitance times the effective resistance, \(\tau = RC\). In the inductive case, the time constant is the effective inductance divided by the effective resistance, \(\tau = L/R\).