6.7 describe how to use two permanent magnets to produce a uniform magnetic field pattern.

If you put two bar magnets very near each other (bar magnets are the ones that are not horseshoe, they look like bars), with their north and south poles facing the magnetic field lines will be parallel. If the magnetic field lines are parallel to each other we have a field of constant strength – this is a uniform field.

6.6 describe experiments to investigate the magnetic field pattern for a permanent bar magnet and that between two bar magnets

Iron filings

1. Place a bar magnet under a piece of paper
2. Shake iron filings onto the piece of paper
3. The shape of the magnetic field can be seen around the bar magnet because of the iron filings attracted to it

Plotting compass

1. Place a bar magnet on a piece of paper
2. Trace around the bar magnet
3. Surround the bar magnet with plotting compasses, arranged in a semicircle; i.e. starting at north and curving around to south (the needle of each plotting compass lines up with the field line, pointing from north to south)
4. Dot where the arrow point sits at each compass
5. remove te compasses
6. join up the dots

(NOTE: this really is not complicated at all, i just couldn't work out an easy way of describing it)

6.5 understand that magnetism is induced in some materials when they are placed in a magnetic field

Some materials that are not magnetic can become magnetic if they are in a magnetic field. In this situation the material acts as a magnet - but only whilst in the magnetic field. This is induced magnetism and only occurs with magnetically soft materials.

6.4 understand the term ‘magnetic field line’

Magnetic field lines are a representation of the shape and direction of a magnetic field.

NOTE: the gaps in the lines to not represent gaps in the magnetic field. Also, a magnetic field is actually 3D, the lines just give an idea of the strength of a field etc.

6.3 describe the properties of magnetically hard and soft materials

Hard

Substances that can be permanently magnetised are known as magnetically hard. They retain their magnetic properties for a long period of time (sometimes permanently) and they are hard to de-magnetise. These are often alloys of iron, nickel and cobalt.


Soft

Substances that can only be temporarily magnetised are known as magnetically soft. They lose all its magnetic properties very quickly (almost as soon as they leave a magnetic field). Alloys with less iron, nickel or cobalt will be magnetically soft and have a weaker magnetic field.

Kinda random note that doesn't really fit anywhere but we need to know: Alloys of iron are called ferrous and those without iron are called non-ferrous.

6.2 understand that magnets repel and attract other magnets and attract magnetic substances

- Opposite poles of magnetism attract (North attracts to South, South attracts to North)
- The same poles repel (North repels North, South repels South)
- Magnetic substances, such as paperclips, can also be attracted by magnets