1. Electricity & Magnetism
Static, Currents, Circuits
Magnetic Fields & Electro Magnets
Motors & Generators

2. Atoms… Have neutrons, protons, and electrons.
Protons are positively charged
Electrons are negatively charged

3. Electrons… Are located on the outer edges of atoms…they can be moved.
A concentration of electrons in an atom creates a net negative charge.
If electrons are stripped away, the atom becomes positively charged.

4. The world is filled with electrical charges:+ - + + + - - + - + + + - - - + + - - -

5. What is this electrical potential called?
Static Electricity - - - - - + + + - - + +

6. Static Electricity
The build up of an electric charge on the surface of an object.
The charge builds up but does not flow.
Static electricity is potential energy. It does not move. It is stored.

7. Static Discharge… or “the shock”
Occurs when there is a loss of static electricity due to three possible things:
Friction - rubbing
Conduction – direct contact
Induction – through an electrical field (not direct contact)

8. Electricity that moves…
Current: The flow of electrons from through a material.
Measured in amperes (amps)

9. How can we control currents?
With circuits.
Circuit: is a complete unbroken path for the flow of electrons. We use wires.

10. There are 2 types of circuits:
Series Circuit: there is only one path for the current to take. If the circuit is broken, all components turn off. As more bulbs (or resistors are added, the bulbs burn less brightly)

11. Series Circuit

12. There are 2 types of circuits:
Parallel Circuit – there are several paths for the current to take. If the circuit is broken at any one branch, only the components on that branch will turn off. As more bulbs (or resistance) is added the brightness does not change.

13. Parallel Circuit

14. Conductors vs. Insulators
Conductors – material through which electric current flows easily.
Insulators – materials through which electric current cannot move.

15. Examples Conductors: Insulators: Metal Water Styrofoam Rubber Plastic
Paper

16. What is Resistance?
The opposition to the flow of an electric current, producing heat.
The greater the resistance, the less current gets through.
Good conductors have low resistance.
Resistance creates heat and transfers electrical energy into light energy.
Measured in ohms.

17. What is Voltage?
The measure of energy given to the charge flowing in a circuit.
The greater the voltage, the greater the force or “pressure” that drives the charge through the circuit.
Examples of a voltage source would be a battery or a generator.

18. Difference b/t Volts and Amps
Example – you could say that…
Amps measure how much water comes out of a hose.
Volts measure how hard the water comes out of a hose.

19. Resistance = Voltage / Current
Ohm’s Law
Resistance = Voltage / Current
Ohms = Volts / Amps

20. Practice with Ohm’s Law
Volts
Amps 4
100 25 15
150 10 2 30 9 45 5 6 48 8