b) Magnetism

Which magnet repel and which magnets attract?

Opposite attract, like repel.

Properties of magnetically hard materials?

Permanently keeps its induced magnetism.

Eg. Steel

Properties of magnetically soft materials?

Loses its induced magnetism quickly.

E.g iron.

Define magnetic field line?

Lines used to show the size and direction of magnetic fields.

Always point North to South.

What does it mean if magnetism has been induced?

When magnetic materials are in a magnet’s magnetic field making it act as a magnet.

Closer the magnet and magnetic material stronger the induced magnetism will be.

How to investigate the magnetic field pattern for a permanent bar magnet and between two bar magnets?

1. Place magnet on top of paper and draw dot at end of magnet.

2. Place plotting compass next to dot and draw new dot at other side of compass.

3. Move compass so that it points away from the new dot and repeat process above.

4. Keep repeating until there’s a chain of dots going across magnet then join dots using smooth curve-this will be the magnetic field line.

5. Repeat whole process several times to create several other magnetic field lines.

6. Repeat whole process for two magnets placed 5cm apart, first facing same pole then facing opposite pole.

How to create a uniform magnetic field pattern using two permanent magnets?

By placing North and South poles of two permenant bar magnets near each other.