As you will probably already know if you are engaged in electronics design at some level, a capacitor is a passive device ...

A parallel plate capacitor with a dielectric filling half the space presents an interesting scenario where the capacitance is affected by the presence and properties of the dielectric material.

All buck converters need capacitors on the input. Actually, in a perfect world, if the supply had zero output impedance and infinite current capacity and the tracks had zero resistance or inductance, ...