Lesson 1.6 Magnets and magnetic fields - teacher’s plan

What do you think is being shown here?

Today I will be able to…

Keywords Magnet

North poleSouth pole

Magnetic materialMagnetic field

Magnetic field line

Describe how magnets interact

To Show how magnetic fields are drawn

Describe the earth magnetic field

Demo

• What happens to a paperclip when it is placed near a magnet?

• What do you think would happen if a piece of cardboard was placed between the paperclip and the magnet?

• What about slotting a piece of metal between the paperclip and the magnet?

• Does it matter which type of metal it is?

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Forces between magnets – experiment

Electromagnet

• http://www.bbc.co.uk/education/guides/z3g8d2p/activity

Worksheet

Questions

• How does a magnet affect the movement of the compass needle?

• How does the strength of the magnetic field vary around a bar magnet?

• How does a compass work?

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1. When two like poles (e.g. two north poles or two south poles) are put together, they repel each other.

Magnetic fields – summary

2. When two unlike poles (e.g. a north and a south pole) are put together, they attract each other.

3. Scattering iron filings around a bar magnet makes it possible to see the lines of force of the magnetic field.

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A magnet can be made by magnetizing a material which is attracted to a magnet, e.g. a paper clip.

Stroke a magnet along the paperclip from one end to the other and then starting from the same place, repeat the movement. The more times this is done, the more magnetic the clip becomes.

Hold a nail in a magnetic field and hit it with a hammer.

Put a magnetic material in a strong magnetic field.

Making a magnet

There are three methods that can be used to make a magnet:

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weakest field further away from poles

What is the shape and direction of the lines of force in the magnetic field around a bar magnet?

N S

Shape of a magnetic field

Where is the magnetic field strongest?

strongest field at poles

strongest field at poles

True or False?

Work out which are true and which are false.

Copy the true ones into your books.

Copy out a correct version of the false statements.

1. Magnetic materials do not have to be touching a magnet to feel an attraction.

2. Magnetic field lines always point from South to North.

3. The magnetic field is weakest when the field lines are close together.

4. The magnetic field is strongest at the poles.

5. Opposite poles repel each other.

Today I will be able to…

Keywords Magnet

North poleSouth pole

Magnetic materialMagnetic field

Magnetic field line

Describe how magnets interact

To Show how magnetic fields are drawn

Describe the earth magnetic field

Use your check point sheet to check off how much you know.CHECKPOINT!