1. Permanent Temporary Electromagnets
Types of magnets
Permanent
Temporary
Electromagnets

2. Magnet
An object that attracts certain materials
Iron and steel

3. Magnets Magnetism: force exerted by a magnet
Magnetic Poles: part of magnet where force is strongest
Every magnet has 2 poles (North & South)
Opposites attract
Like repel
Break a magnet = 2 new magnets

4. Magnets
Magnetic field: region around magnet in which magnet exerts force
Magnetic
field lines

5. Magnets
Magnetic domain: group of atoms whose magnetic fields are aligned

6. Magnets Permanent and temporary magnets Drop
Expose to high temperatures
Earth: magnetic field

7. Electromagnetism Magnetism that results from an electric current
Charge particle---electron---moves and creates a magnetic field

8. List 3 ways that the strength of an electromagnet can be controlled.
What are the 2 benefits of an electromagnet?

9. Electromagnet
Magnet made by placing a piece of iron or steel (ferromagnet ic core) inside a coil of wire

10. Electromagnet

11. Electromagnet Can be turned off and on
Can control the strength of the magnet
Voltage source (increase = increase strength)
# times coil is wrapped around the core (increase # = increase strength)
How close together the coils are (closer = increase strength)
Size of ferromagnetic core (increase size = increase strength)

12. Magnets--Current Magnets can be used to generate electric current.
Generator: a device that converts the energy of motion (kinetic energy) into electrical energy
Shaft of generator turns
Rotation of shaft causes coils of wire to spin---creates a magnetic field
Coils cross magnetic field line-----electric current created

13. Magnets--Current Direct current Electric charge flows in ONE direction
Produced by batteries
Alternating current
Flow of electric charge that reverses direction at regular intervals
Home and school

14. Magnets--Current Transformer
A device that increase or decreases voltage
Use magnetism to control the amount of voltage
Consists of 2 coils of wire wrapped around an iron ring

15. Magnets--Current
Watt
Unit of measurement for power