Fortunately a variable capacitor is a surprisingly simple device ... expect a similar coil to form the inductive part of a tuned circuit, but this coil is shorted out to prevent its inductance ...

Capacitors with unique construction and failure modes are placed on the AC line to manage EMI modes and ensure user safety.

using the terminal characteristic for a capacitor: i = C dv/dt. 1. Construct a simple RC high pass filter circuit, using your capacitor. 2. With input level constant, sweep the input over a wide range ...

While they are simple, they waste a lot of energy ... Of course, the inductor and capacitor also form a resonant circuit which can interact with the PWM frequency, but for now, I am literally ...