Electric Motor & Generator

An Interactive Lesson on Electromagnetic Principles

How They Work

Electric motors and generators are two sides of the same electromagnetic principle. They both rely on the interaction between magnetic fields and electric currents.

Electric Motor
Electric Generator

Electric Motor

An electric motor converts electrical energy into mechanical energy. It works through the interaction between:

  • A magnetic field (usually from permanent magnets)
  • An electric current flowing through a coil

When current flows through the coil, it creates a magnetic field that interacts with the field from the magnets, causing the coil to rotate.

Key Principle: The motor effect - when a current-carrying conductor is placed in a magnetic field, it experiences a force.

Electric Generator

An electric generator converts mechanical energy into electrical energy. It works through electromagnetic induction:

  • A coil rotates in a magnetic field
  • This motion induces an electric current in the coil

The direction of the current changes as the coil rotates, creating alternating current (AC).

Key Principle: Faraday's Law - a changing magnetic field induces an electromotive force (voltage) in a conductor.

Key Components

Both devices share similar components:

  • Stator: The stationary part that provides a magnetic field
  • Rotor: The rotating part with coils of wire
  • Commutator: Reverses current direction in motors (not always in generators)
  • Brushes: Conduct electricity to/from the moving commutator

Interactive Visualization

Current Flow (Positive)
Current Flow (Negative)
Magnetic Field (N)
Magnetic Field (S)

Current State: Electric Motor - Converts electrical energy to mechanical rotation.

Rotation Speed: Medium

Direction: Clockwise

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