1. Warm Up #16
How is Earth a magnet?

2. Lesson 1: Magnets and Magnetic Fields
Ch. 10 Magnetism
Lesson 1: Magnets and Magnetic Fields

3. Essential Questions
What types of forces do magnets apply to other magnets?
Why are some materials magnetic?
Why are some magnets temporary while others are permanent?

4. What does magnetic mean? ACTIVITY
Of the following items, which ones are magnetic?

5. Magnets Magnet – any object that attracts the metal iron
BrainPop - Magnetism

6. Magnetic Poles
Magnetic pole – a place on a magnet where the force it applies is strongest
Magnetic force – a force of attraction or repulsion between the poles of 2 magnets
Becomes stronger as magnets move closer together
Becomes weaker as magnets move farther apart

7. Magnetic Fields
Iron filings form a pattern of curved lines that reveal the magnet’s magnetic field
The lines are closest together at the magnet’s pole, where the magnetic force is strongest
As lines become farther apart, the field and force become weaker

8. Magnetic Materials
Magnetic material – any material that is strongly attracted to a magnet
Ferromagnetic elements – elements, including iron, nickel, and cobalt, that have an especially strong attraction to magnets

9. Magnetic Materials
Not all materials are magnetic but a magnetic field does surround every atom that makes up all materials
The field is created by the atom’s constantly moving electrons
The interactions of these individual fields determines whether a material is magnetic

10. Magnetic Materials
Magnetic domain – a region in a magnetic material in which the magnetic fields of the atoms all point in the same direction
In most materials, the magnetic fields of the atoms point in different directions
As fields around atoms combine, they cancel each other out causing most types of matter to be nonmagnetic materials

11. How Magnets Attract Magnetic Materials
Temporary magnet – a magnet that quickly loses its magnetic field after being removed from a magnetic field (Video)
Permanent magnet – a magnet that remains a magnet after being removed from another magnetic field

12. A Temporary Magnet ACTIVITY
Stroke a nail with a magnet 30 times.
Touch nail to a pile of paper clips.
What happens?
What do you think will happen if the nail is stroked more than 30 times?
What do you think will happen if the nail is stroked less than 30 times?