electromagetism and magnetism

What happens when two magnets are brought close together?

They exert a non contact force on eachother

what is repulsion

if the poles are the same then they will repel eachother

what is attraction

If the poles are different then they will attract eachother

what is a permanent magnet

a magnet which produces its own magnetic field and is always there

what is a induced magnet

a object that becomes magnetic when placed in a magnetic field

what happens when a induced magnetic is removed from its magnetic field ?

It will lose most or all of its magnetism

what happens when a electric current flows through a wire?

it will produce a magentic field around the wire. The field is made up of concentration circles perpendicular to the wire with the wire in the centre

how do you increase the field strength

the field strength increases with :

• greater current

  • closer to the wire

how are you able to see that the concentration circles are perpendicular to the wire ?

by a placing a compass near a wire that is carrying the current. As you move the compass it will trace the direction of the magnetic field.

what is electromagnetism

when electric currents produce their own magnetic fields

what happens when you change the direction of current ?

it will change the direction of the magnetic field

describe how you use the right hand thumb rule

you do this to work out which way the magnetic field goes. Use your right hand and point your thumb in the direction of the current and curl your finger. The direction of your fingers is the direction of the field