# Ideal circuit elements

Introduction to the most common circuit elements: resistor, capacitor, and inductor.

## At 4:11, a special notation from calculus: $dv/dt$

$i = \text C\,\dfrac{dv}{dt}$

$d$ is calculus notation for 'differential', or "a tiny change in ...". For example, $dt$ means 'a tiny change in time'. When you see it in a ratio, like $dv/dt$, that means, "a tiny change in $v$ (voltage) for each tiny change in time" An expression like $dv/dt$ is called a derivative. The derivative is the slope of voltage as it changes over time. When voltage changes rapidly across a capacitor, the current is high.

Created by Willy McAllister.