Before we go any further, we need to know something fundamental first.

RC circuit: a circuit made by resistor and capacitor.

RL circuit: a circuit made by resistor and inductor.

LC circuit: a circuit made by inductor and capacitor.

RLC circuit: a circuit made by resistor, inductor and capacitor.

Why use L instead of I to represente Inductor?

Well, maybe simplly because we already represented current using I.

Current: $$\begin{align*} &1kA = 10^3A & 1mA = 10^{-3}A \\ \\ &1\mu A = 10^{-6} \end{align*}$$

Capacitance: $$\begin{align*} &1\mu F = 10^{-6}F & 1pF = 10^{-12}F \end{align*}$$

Inductance: $$\begin{align*} &1mH = 10^{-3}H & 1\mu H = 10^{-6}H \end{align*}$$

我会在看完可汗学院的关于本章内容的视频之后详细地记录本章知识，但现在, 先跟中文书和老师走。