thevenin and norton theorem solved problems -Electricaldiary

 What is DC Motor? 

A DC motor is an electrical device that converts electrical energy into mechanical energy.DC Motor runs on DC Current. The Construction and working principles of the DC Motor and DC Generator are the same. The only difference is the direction of power flow.DC motor is fed by electrical energy and gives mechanical energy, whereas DC Generator is fed by mechanical energy and gives electrical energy as output. 

Working Principle of DC Motor

The Working Principle of Dc Motor is based on Lorenz's force which is stated asWhen a current-carrying Conductor is placed in the influence of magnetic field then this current-carrying conductor experiences a force perpendicular to the direction of the current vector and length vector of the conductor and is stated as follow:-

F =I(L X B) Newton

where 

I = Current in Ampere

L=Length of the Conductor

B = Magnetic Flux Density in tesla

 F = Induce force on the Current carrying Conductor

The direction of the induced force is given by Fleming Left-Hand rue

Fleming Left-Hand rue

if we stretch our first three-finger i.e(thumb, forefinger, and Middle finger) of the left hand then if the middle finger is pointed in the direction of the magnetic field, forefinger in the direction of the current flowing then the direction of the experience force by the current-carrying conductor is given by the thumb's direction.

Working of DC Motor

(Image Source. Wikipedia)

When the armature of the motor is connected to the external source of electric supply in the presence of a magnetic field then a force is experienced by the armature conductor due above mention theory. The magnetic field in the stator is provided by either a permanent magnet or a magnetic field system. To maintain unidirectional force on the conductor, a commutator is used.