1. Magnets, Magnetism & Electromagnetism

2. Magnets and Magnetic Fields
Magnets can be classified as ferromagnets, electromagnets, temporary magnets, and permanent magnets.
A material is magnetic if its domains line up
Magnetic materials include iron, nickel, and cobalt
Every magnet is surrounded by a magnetic field. The shape of the field can be shown with magnetic field lines.

4. PERMANENT
ELECTROMAGNET
TEMPORARY
FERROMAGNET

5. Domains – regions of aligned electron spins

6. Making Magnet Need a ferromagnetic material Need to align the domains
Can be done with electricity
Can be done with the force field of another magnet

7. Ferromagnetic Materials

8. Magnetic Field – Lines of Force

9. Magnets and Magnetic Poles
All magnets have two poles. The north pole will always point to the north if allowed to rotate freely. The other pole is called the south pole.
Like magnetic poles repel each other.
Opposite magnetic poles attract.

11. Lines of Force – Attracting Magnets

12. Lines of Force – Repelling Magnets

13. Electromagnetism
Pushing a magnet through a coil of wires generates electric current

14. This coil of wires is called a SOLENOID
Electromagnetism
Flowing electricity creates a magnetic force field
This coil of wires is called a SOLENOID

15. Electromagnetism
Add an iron core and you create an electromagnet

16. Advantages of Electromagnets
Can be turned off and on
Can be made stronger
Polarity can be reversed