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Differences between Inductors and Capacitors

21. June 2015 14:39 by arria in



The inductor is opposing to a change in current: V = L * di/dt

The capacitor is opposing to a change in voltage: i = C * dV/dt

Stores energy as Magnetic Field depending on material magnetic permeability. Energy stored = 1/2 * L*I^2

Stores energy as Electric Field depending on material electric permittivity. Energy stored = 1/2*C*V^2

Z=0 @ 0 Hz (DC); Z= infinite @ high frequencies

Z= infinite @ 0 Hz (DC); Z= 0 @ high frequencies

Current lags behind Voltage  by π/2

Voltage lags behind Current by  π/2

Series Inductors combine like series resistors.

Parallel Inductors combine like parallel resistors.

Series Capacitors combine like parallel resistors.

Parallel Capacitors combine like series resistors.