GCSE PHYSICS - MAGNETISM AND ELECTROMAG - LESSON 12 - motor effect

What is the Motor Effect?

Definition and Basic Concept

• The motor effect describes how a current-carrying conductor experiences a force when placed in a magnetic field. This interaction results in movement of the conductor.

Experimental Setup

• A simple experiment illustrates the motor effect using two supporting conducting rods and a free-moving conducting rod positioned between magnets with opposite poles (north-south). The setup allows for movement when an electric current flows through the circuit.

Current Flow and Force Direction

• When the switch is closed, electric current flows through the free-moving rod, which remains in contact with supporting rods. The typical current used ranges from 2 to 4 amps, generating a force that pushes the rod either to the right or left based on current direction and magnet polarity.

Magnetic Field Interaction

• The magnetic field produced by the current creates concentric circles around it, while external magnets produce fields directed from north to south. The interaction leads to varying magnetic field intensities on either side of the conducting rod, resulting in a net force pushing it towards one side.

Changing Force Direction

• Reversing either the direction of current flow or swapping magnet poles alters the direction of force acting on the conductor:

• Keeping current constant but switching magnet poles causes force to act leftward.