How is the rms current in the capacitor related to its capacitance and to the frequency? The answer, which requires

Capacitors in AC Circuits
In analogy with resistance, we write:

Capacitors in AC Circuits

RC
Circuits

RC
Circuits
This phasor diagram
illustrates the phase
relationships. The
voltages across the
capacitor and across the
resistor are at 90
°
in the
diagram; if they are
added as vectors, we
find the maximum.

RC
Circuits
This has the exact same form as
V
=
IR
if we
define the impedance,
Z
:

RC
Circuits

RC
Circuits