| Work of electric current is converted to heat. The
equivalency between alternating current (AC) and direct current (DC)
can be understood by comparison of the beat that AC and DC generate,
separately. For experimental proof, prepare two cups that contain
same amount of water. Then insert resistors of the same value to each
and apply an AC current and a DC current respectively. Adjust the
current to create the equal water temperature over a given time (Heat
generated by each resistant is same). At this time, we find that the
value of the DC current is 1/1.4142 of the peak value of the AC current.
It is called an effective value to measure a work of an alternating
current. |
|
What
is an effective or a root mean square value of an alternating current and
of an alternating voltage?
An
effective value of an alternating current is root mean square of its instantaneous
value over one cycle. This is 1/1.4142 of the peak current value for a normal
(= sinusoidal) alternating current. An effective value of an alternating
voltage is defined in the same manner. It is 1/1.4142 of the peak voltage
value.