Electric Motor

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Slide 1

Electric Motor

By Princess Barcega

APG School

Slide 2

Magnetic Force On A Current – Carrying Conductor

The magnetic force (F) the conductor experiences is equal to the product of its length (L) within the field, the current I in the conductor, the external magnetic field B and the sine of the angle between the conductor and the magnetic field. In short

F= BIL (sin)

Slide 3

The force on a current-carrying conductor in a magnetic field:

When a current-carrying conductor is placed in a magnetic field, there is an interaction between the magnetic field produced by the current and the permanent field, which leads to a force being experienced by the conductor:

Slide 4

The magnitude of the force on the conductor depends on the magnitude of the current which it carries. The force is a maximum when the current flows perpendicular to the field (as shown in diagram A on the left below), and it is zero when it flows parallel to the field (as in diagram B, on the right):

Slide 5

Fleming’s left-hand rule

Slide 6

The directional relationship of I in the conductor, the external magnetic field and the force the conductor experiences

I

F

B

Slide 7

Motion of a current-carrying loop in a magnetic field

N

S

L

R

I

F

F

Rotation

Commutator (rotates with coil)

brushes

Slide 8

Vertical position of the loop:

N

S

Rotation

Slide 9

Electric Motor

An electromagnet is the basis of an electric motor

An electric motor is all about magnets and magnetism: A motor uses magnets to create motion.

Opposites attract and likes repel. Inside an electric motor, these attracting and repelling forces create rotational motion.

A motor is consist of two magnets.

Slide 10

Parts of the Motor

Armature or rotor

Commutator

Brushes

Axle

Field magnet

DC power supply of some sort

Slide 11

Motor Illustration