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Electric Motor
A device which converts electrical energy into mechanical energy is called an electric

motor.
Principle: Electric motor works on the principle that a current carrying conductor placed
in a magnetic field experiences a force.

Construction of an electric motor :

Parts of a Electric Motor
i) Armature coil ABCD – It consist of a large number of turns of insulated copper wire
wound around a rectangular iron core ABCD.

ii) Strong magnet : The armature coil is placed between the poles of a strong magnet (N &
S) to create a strong magnetic field.
iii) Split ring commutator : A metallic ring divided into two halves (R 1 & R 2). The ends of the

armature are connected to the two rings. This commutator helps to reverse the direction
of the current in the armature coils.
iv) Brushes : Two carbon brushes B 1 & B 2 are used to press upon the commutator.
v) Battery : It supplies the current (D.C) to the armature coil.
Working
i. When a current is switched on, the armature coil ABCD, due to the action of the magnetic,
the arm AB experiences a force in the downward direction & arm CD in the upward