Magnetism

What are soft magnetic material ?

materials which are easy to magnetise , and they easily loose their magnetism

What are hard magnetic material ?

Materials which are difficult to magnetise and they have a permanent magnetism

What does the magnetic field represent?

They represent strength , direction and size

Uniform magnetic field

created when two unlike poles held together .Has the same strength and direction

What are the two types of magnets ?

Permanent magnet

Induced magnet

Permanent magnet

produces its own magnetic field

Is permanent magnetic made from permanent magnetic material ?

Yes

Induced magnet

when a magnetic material os placed in a magnetic field and can be a magnet temporily

What is electromagnetism ?

when a currrent carrying wire creates a magnetic field around it

What will happen if direction is reversed?

the magnetic field will be reversed

Motor Effect

it is when two magntic fields interact to produce a force on the wire

Factors affecting motor effect

speed of coil

direct of rotation of coil

number of turns

force

Ways to increase the dc motor

increase the current in the coil

use a stronger magnet

increase number of turns