phys test 24

Attract

To pull towards each other. This is what opposite poles of a magnet do

Cobalt, iron, steel and nickel

The only magnetic materials

Compass needle

A piece of magnetic material which is free to move so that it will point to the Earth's magnetic north pole. It will also point to the south pole of a bar magnet.

Magnetic materials

Materials which are attracted to a magnet

Non-magnetic materials

Materials which are not attracted to a magnet

Repel

To push away from each other. This is what similar poles of a magnet do (eg. two north poles)

Magnetic field

The area around a bar magnetic where a magnetic material experiences a force.

Magnetic field lines

These show the direction in which a compass would point if it was placed at that position

Copper, Aluminium, Zinc, Brass

These are examples of metals which are not magnetic.

Why do magnets sometimes float?

The magnetic forces balances the weight force.

Force = mass x acceleration

An equation to find the force requires to accelerate a mass

Weight = mass x gravitational field strength

The equation to find the weight force experienced by a mass on Earth's surface.

Magnetic field lines point from..

..a north pole to a south pole of a bar magnet