Drawing Magnetic Fields

Magnetic Field Shape

The region around a magnetic where a force acts on a magnetic material is called the magnetic field.

Magnetic materials are either:

  • Iron
  • Steel
  • Nickel
  • Cobalt

The force between a magnet and a magnetic material is always an attractive force.

The magnetic field looks like this:

Drawing Magnetic Fields, figure 1

Yes, you might be asked to draw it - don’t forget to put in the arrows! Notice how the field comes out of the north and into the south.

The strength of the field is strongest at the poles of the magnet. The further away from the poles, the weaker the field and the weaker the force.

Identify Field

A compass contains a small bar magnet. The Earth has a magnetic field around it.

The needle of a compass points in the direction of Earth’s magnetic field. This provides evidence that the Earth’s__ core__ is made up of a magnetic material.

We can use this knowledge to be able to use a compass to plot the magnetic field around a magnet:

Drawing Magnetic Fields, figure 1

One can the plot the points of the compass to draw out the magnetic field.

Earth’s Core

We can use compasses to show the direction of Earth’s magnetic field. This also shows that Earth has a magnetic field since the compasses align themselves with Earth’s field.

The needle of a compass points to the North pole. This means that this is Earth’s magnetic South pole. As we can see from the diagram above, the field goes into the South therefore this is where Earth’s magnetic South is situated.

The closer to the pole of a magnet the stronger/weaker the field.
stronger
The closer to the pole of a magnet the stronger/weaker the field?
stronger
How can we use a compass to plot a magnetic field around a bar magnet?
compass points in the direction of the field
Explanation: The compass will point in the direction of the field
Where in the world is the magnetic North pole?
Your answer should include: south pole / antarctica