Dc Motor-Principle

We have often come across the term Motor.But many of us don't know what exactly is a motor? And What it does? In this section lets see what is a motor and how motor works..

Motor:
Motor is a device which converts given electrical energy into mechanical energy.

So how the motor converts electrical energy into mechanical energy?

Before going into the principle of electric motor, we have to know a basic rule:FLEMING'S LEFT HAND RULE.

What is Flemings left hand rule?

Flemings Left hand rule shows the direction of the motion of the conductor carrying current in the magnetic field. (or) left hand rule shows the direction of thrust on the conductor carrying current in magnetic field.

According to LHR... The thumb,first finger and middle finger of left hand is held mutually perpendicular to each other as shown in fig.

-> First finger shows the direction of field.

-> Middle finger shows the direction of current.

Then
-> Thumb shows the direction of motion of conductor.



Principle Of Motor:

The working of motor is based on the principle that whenever a current carrying conductor is placed in a magnetic field it experiences a force in the direction as shown by flemings left hand rule.

The magnitude of resultant force is given by:

F=BIl Newton

where
B is the Magnetic Field.
I is the current carried by conductor
l is the length of the conductor.

The principle of motor diagram is shown above.