AC Generator

See how mechanical rotation in a magnetic field generates AC voltage.

The Concept: Generating EMF

An AC generator is a direct application of Faraday's Law. By rotating a coil of wire in a constant magnetic field, the magnetic flux ($\Phi_B$) through the coil continuously changes. The maximum change occurs when the coil is parallel to the field, inducing the highest voltage. The change is zero when the coil is perpendicular, inducing zero voltage. This process creates a sinusoidal Alternating Current (AC).

How to Use the Lab

  • Press Start to begin rotating the coil.
  • Observe the highlighted magnetic flux lines passing through the coil.
  • The light bulb glows according to the induced current.
  • Adjust the Rotation Speed ($\omega$) and B-Field Strength to see their effect on the output.

Controls

Live Analysis

$\mathcal{E}(t) = -\frac{d\Phi_B}{dt}$

Generator

Output Voltage (EMF)