1. Unit 8 Magnetism `

2. Magnetic Properties Permanent Magnets Permanent magnet
Poles (north and south)
If you chop them in half, each half still has a N and S pole
Like poles repel
Opposite poles attract
Permanent magnet
naturally magnetic materials
iron, cobalt, and nickel

3. What makes materials magnetic?
Groups of atoms that have aligned electrons are called domains
domains are aligned in permanent magnets

4. Magnetic Field
Every magnet creates a magnetic field in the space around it
This is how magnets have forces between them without even touching

5. Electromagnets
an electrical current passes through a coil of wire wrapped around some iron
more current, stronger magnet
Can be turned on and off

6. Electromagnetic induction
Flowing current induces a magnetic field
a moving magnet induces electrical current to flow

7. Electric Motor converts electrical energy into mechanical energy
A current causes an electromagnet to rotate

8. Electric Generators Converts mechanical energy into electrical energy
A coil of wire rotates within a magnetic field-generates a current
Generator simulation

9. Making electricity
Begin with fuel (chemical energy- fossil fuels) or another form of energy (nuclear, solar, hydro)
Convert from one form of energy into mechanical energy (turn turbine- large fan)
Turbine will rotate a magnet in a coil of copper wire (generator!!)
Electrons flow in the wire…viola..electricity

10. Energy conversion

11. Transmitting electricity
Increase voltage for travel
Decrease voltage when at your home
Use transformer – electrical device that changes voltage