Spark image

When a wire carrying a current is in a magnetic filed there is a force on it.

The magnetic field that makes the wire move is called a CATAPULT FIELD because of its shape.
The diagrams show:
(i)the field of two flat magnets
(ii) the field of a wire
(iii) the result of putting the wire and magnets together.
It is this third field that is called the catapult field.

The magnetic lines of force are close together near the wire so forcing it upwards.
If the current direction is reversed the wire will be forced downwards.

© Keith Gibbs 2009