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a)
Commutator
-They are the split - rugs which reversed the current in the coil every half-cycled and hence allow rotation to continue.
b) They provide electric connection to the coil.
c)
-The lengths AB and CD of the coil are current carrying conductors in a strong magnetic field which is perpendicular to the wires.
-Each side of the coil has force acting on it
-AB has a downward force while CD experience and upward force.
-Overall the coil experiences an anticlockwise motion.
d)
-Increasing the amount of current
-Increasing the strength of magnetic field
-Using more turns in the coil
-Winding the coil on a soft iron core
Wilfykil answered the question on March 26, 2019 at 05:31
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