1. Notes 8-1: Magnetism

2. Magnetic Force and Fields
Opposite Poles attract (north to south)- like charges repel Strength increases as magnets move closer together
Magnetic Field- force that surrounds the magnet- field is strongest close to the magnet Fig 2 pg 225
Magnetic Poles- where the magnetic force are the strongest. All have North and South Pole

3. Compass
A magnet that is free to rotate can turn when it is placed in a magnetic field.
Compass has needle or a small bar magnet that can freely turn.
Fig 6 pg 227

4. Earth’s Magnetic Field
Earth acts like a giant bar magnet and is surrounded by a magnetic field that extends into space.
South currently at the Magnetic North Pole
Fig 6 pg. 227

5. Magnetic Materials What materials are magnetic?
In the atoms of most elements, the magnetic properties of the electrons cancel out.– Metals that are magnetic—these electrons do not cancel out when brought near a magnet.
Iron, Cobalt, Nickel

6. Magnetic Domains
Like poles always point in the same direction. Fig. 7 pg 229
Temporary magnets realign domains

7. Temporary Magnets
Domains in magnetic material have a random orientation
Magnets will realign domains in magnetic material to face the same direction, giving it magnetic properties

8. Permanent Magnets
Strong magnetic field in material prevents the domains from vibrating out of alignment
Even if magnet is cut in half, a north and south pole will form
Permanent Magnets can be demagnetized by heat