DC Motor


 
 
Concept Explanation
 

Electric Motor

An electric motor is a rotating device used for converting electric energy into mechanical energy.

Principle:

An electric motor is based on the principle that when a rectangular coil is placed in a magnetic field and current is passed through it, two equal and opposite forces act on the coil which rotates it continuously.This force which rotates the coil is called as torque.

Construction:

It consists of a rectangular coil, say ABCD connected to a source of current and a switch. The commutators P and Q are fixed to the coil and pressed tightly against brushes X and Y. The function of commutator is to reverse the direction of current flowing through the coil every time, the coil passes the vertical position, i.e. after every half rotation in electric motor. In electric motor, split rings acts as commutator. The brushes are two flexible metal plates or the carbon rods which are so fixed that they continuously touches the revolving rings.

Working:

Electric motors involve rotating coils of wire which are driven by the magnetic force exerted by a magnetic field on an electric current. They transform electrical energy into mechanical energy.

The speed of rotation of the motor can be increases by:

1. Increasing the strength of the current in the coil.

2. Increasing the area of the coil.

.... (More Text Available, Login?)
Sample Questions
(More Questions for each concept available in Login)
Question : 1

Out of these _______________ uses of DC motor .

Right Option : C
View Explanation
Explanation
Question : 2

The speed of rotation of the motor can be increases by _________________.

Right Option : D
View Explanation
Explanation
Question : 3

An electric motor

Right Option : D
View Explanation
Explanation
 
 


Students / Parents Reviews [10]