ELECTRICAL ENGINEERING
Direct and alternating voltage
Compare constant polarity with voltage that periodically reverses polarity.
INTERACTIVE EXAMPLESIMULATION
The principle
In this simple DC example polarity stays constant. AC voltage periodically reverses polarity. The sine wave shown is common, but AC does not have to be purely sinusoidal. Current also depends on the load.
An example
Switch between DC and AC and change the number of periods. The vertical axis is voltage, not automatically current through a load.
Important
The shown amplitude is a peak value. For a pure sine wave, RMS voltage equals peak voltage divided by √2.