1. Electricity Section 1: Electric Charge and Static Electricity

2. Atoms and their charges Atoms: –Protons = positive charge –Electrons = negative charge –Neutrons = no charge –CHARGED OBJECTS EXERT FORCES ON EACH OTHER

3. Law of Electric Charges The type of force between objects depend on the type of charge the object has –If the charges are the same or if the charges are different from each other –Like/same charges repel away from each other –Different charges attract each other

4. Page 159 – Figure 1

5. Electric force and field Force between the two charged objects –Strength of force depends on: Size of the charges and distance between them The force between charges creates an electric field

6. Pg 160 – Figure 2

7. How do atoms become charged? Atoms are neutral until they become charged –To become charged – gain or lose electrons

8. Ways to become Charged… Friction: rubbing two objects together –Electrons are wiped from one object and transferred to the other object

9. Ways to become charged… Conduction: electrons are transferred from one object to another through direct contact

10. Ways to become charged… Induction: charges in an uncharged object are rearranged without direct contact with a charged object

11. Conservation of Charge No charges are created or destroyed just rearranged

13. Static Electricity Build up of electric charges on an object Static = not moving

14. Conductors versus Insulators Conductors Charges move easily Most metals are good conductors Tap water is also a good conductor Used to make wires – transfer charges Insulators Materials where charges can not easily move Electrons are tightly bound to the atoms of the insulating material Examples are plastic, rubber, glass, wood and air

15. Conductor vs. Insulator

16. Electric Discharge Loss of static electricity on an object as charges move off an object Lightning is an example of Electric Discharge

19. Lightning Rods Rod connected to the ground by a wire. On top of tall buildings -helps direct discharged electric charges to travel to the ground (become grounded).