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FIGURE 5. MAGNFTIC FORCE ON A CONDUCTOR
Interacting magnetic forces on a current
carrying loop in a magnetic field tend to
produce rotational movement of the
conductor.
FIELD MAGNETS
SPLIT RING
COMMUTATOR
CURRENT FLOW
(CONSTANT)
BRUSHES
BASIC MOTORS
MOTOR OPERATION
Current flows from the battery through the armature
conductor when the brushes contact the two
commutator bars. This creates magnetic fields around
the conductor. Current also flows through the field
windings creating a powerful magnetic field. In
FIGURE 6. current from the battery flows first around
the right–hand field coil and then crosses over to flow
around the left–hand field coil. Current then flows
through the left–hand brush, the armature winding and
current returns through the right–hand brush to the
battery. The magnetic fields around the conductor will
be in the directions shown by the circular arrows. The
left–hand side of the armature winding will be pushed
upward and the right–hand side downward producing
clockwise rotation.
DIRECTION OF ROTATION
BATTERY
BATTERY
FIGURE 6. MOTOR OPERATION
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