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direction. These forces are equal in magnitude & opposite in direction. This force rotates
the coil in clockwise direction until it becomes vertical.
ii. In this position, the contact between the commutator & the brushes breaks & the supply
of current to the coil is cut off. Hence, no force acts on the coil. But the coil continues to

rotate due to the principle of inertia.
iii. The commulator again comes in contact with the brushes. The current once again passes
through the coil. This sets the arm AB in rotation. As the arm AB completes one rotation
0
0
from 90 to 360 , downwards & the arm CD moves upwards. This force again moves
the coil in a clockwise direction.
iv. Thus, the electrical energy helps the coil to rotate in the same direction. Hence, the coil of
the motor continues to move in the same direction & the electrical energy of DC is
converted into mechanical energy.

Uses/ applications of a DC motor.
1. These motors are used in domestic appliances like mixtures, blenders,
refrigerators & washing machines.
2. These motors are used in electric fans, hair dryers, record players, tape

recorders & blowers.
3. These motors are used in electric cars, rolling mills, electric cranes, electric lifts
& electric trains, etc.