AC vs DC Current Simulator

Compare a constant DC polarity with a sinusoidal AC source using explicit peak, RMS, and direction conventions.

Direct Current (DC)

=+-+ 120VLoadI constant direction
V(t) = constant
V = 120 V
Convention: the loop shows a fixed source polarity, so conventional current keeps one direction.
Electron drift in a metal would be opposite to conventional current.

Alternating Current (AC)

~ 120V peakLoadi(t) reverses direction
V(t) = Vpeak × sin(2πft)
Vrms = Vpeak / √2 = 84.9 V (sine wave)
V(0.0s) = 120 × sin(2π × 1 × 0.0)
Vinstant = 0.0 V
Current direction reverses every half-cycle. Right now the source is in the positive half-cycle.
The dashed motion is schematic oscillation, not a literal electron path length.

Legend

→
Current arrowIndicates the conventional current direction or the instantaneous AC direction being discussed.
+ / -
DC polarityMarks the fixed source polarity for the DC example.
~
AC source labelShows a sinusoidal source, here labeled by peak voltage rather than RMS.