电阻，电容，电感（resistor, capacitor, inductor）

电阻：   实例：

电容：        实例：

电感：   实例：

is the angular frequency of the AC current,

is the imaginary unit.

http://en.wikipedia.org/wiki/Electrical_resistance_and_conductance

http://en.wikipedia.org/wiki/Resistor

http://en.wikipedia.org/wiki/Capacitor

http://en.wikipedia.org/wiki/Inductor

http://www.dz3w.com/info/application/0079156.html

http://www.facstaff.bucknell.edu/mastascu/elessonshtml/LC/Capac1.htm