Answer Posted / nagendra murthy
any DC motor or generator will need to have a commutator. A
commutator is a device used to change the direction of
current flow through the motor. The reason a cummutator is
needed is because a DC current in a magnetic field can only
turn the motor through 180 degrees, after which the force
will cause the motor to return to a fixed position. In order
to make the force turn the motor the current needs to be
changed every 180 degrees so that the force will act in the
opposite direction, spinning the motor around. This is
achieved using a commutator. The commutator is normally a
device which brushes against terminals in the motor. As the
motor turns the terminals in contact with the brushes
change, and so does the current.
Is This Answer Correct ? | 18 Yes | 2 No |
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