BELIEVE ME NOT!   A SKEPTIC's GUIDE
Next: The Differential Equation
The term "AC" stands for "Alternating Current",
typically the 60 Hz power available from any North American
electrical outlet.^{21.1}
A complete discussion of AC circuits must involve the
"inertial" effect of inductance, but a useful
introduction can be developed using only
capacitance and resistance .
We begin by picturing a generic series circuit driven by a
sinusoidal voltage
.
It is convenient to use the complex form^{21.2}for calculations;
just remember that none of the actual physical quantities
like current or voltage will actually have a measurable
imaginary part.^{21.3}
The voltage amplitude is taken to be pure real.
Figure:
An circuit driven by an AC voltage.

Footnotes
 . . . outlet.^{21.1}
 In Europe and much of Asia
the standard is 50 Hz.
 . . . form^{21.2}
 Here
signifies "the real part of" a complex quantity like
.
The imaginary part is written (e.g.)
.
 . . . part.^{21.3}
 Let me know if you invent
an imaginary voltmeter!
Jess H. Brewer 
Last modified: Mon Nov 16 18:06:18 PST 2015