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Electric Motor.
Electric motors have a wide variety of uses.
The catapult effect
(motor effect) is used to make a
simple electric motor.
The wire is pushed in the opposite direction
if the direction of the current through it is reversed.
In a motor, the wire is
wound around a central block called an
armature.
A spindle through the armature allows it to rotate.
The current flows in opposite directions
on each side of the armature,
so one side is pushed while the other is pulled.
This makes the armature rotate.
After the armature has rotated
through half a turn (180°),
then the side of the armature being pushed
upwards in the above picture
is now on the left and the
side being pulled down on the right.
The armature would be trying to turn
in the opposite direction.
For the armature to continue
to spin in the same direction,
the direction of the current flowing through the wire
must be reversed every half
turn.
This is achieved using a split - ring
commutator (see next page).
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Copyright © 2008 Dr. Colin France. All Rights Reserved.