1. 1

2. 7.1 Static Charge Static electricity is electric charge that can be held in one place Electrons have a negative charge, protons have a positive charge, neutrons are neutral An atom/material with equal numbers of electrons and protons is neutral An neutral atom/material becomes charged when electrons transfer in or out of the material An insulator does not allow electric charge to move easily A conductor is a material in which electric charges can move more easily A coulomb is the unit used to measure charge 2

3. What are some examples of static charge? 3 clingy clothes from the dryer Static charge in hair after combing Static charge buildup in storm clouds prior to lightning discharge (pg. 264) Shuffling across the carpet builds static charge and touching metal discharges it

4. 4 Electron Negatively charged Neutron No charge Proton Positively charged Proton Positively charged The Atom

5. s d 5 Friction & Electron Transfer Friction Electron transfer

6. Positive Neutral Negative Charge Charge Charge + - + - + - + - + - + - + - + - + - + - + + - - + + - + + - + + - + - - - + - - - + - + - + - + - + - - - + - - - + - - 6

7. Static charge is an electric charge that can be collected and held in one place What is Static Charge? 7

8. What Force produces a Static Charge? 8 The Force of FRICTION

9. - - - - - - +++++++++++- + - + - + - + - + - + - + 9 Conductors & Insulators Electron Current can flow most freely Electrons can spread evenly along a conductor Can not retain a static charge Resist the flow of Electron Current Only insulators can retain a static charge

10. Conductor or Insulator ConductorInsulator goldglass platinumplastic silveracetate aluminumdry wood carbon (ex. graphite pencil “lead”)wool waterballoon human skin (semi-conductor)human hair 10

11. How did early scientists detect Static Charge? The Electroscope! 11 f

12. The UNIT of electric charge is called a… Coulomb It takes the addition or removal of 6.25 X 10 18 electrons to produce 1C of charge How Electric Charge is Measured 12

13. 13 Metal Dome Belt Insulator Motor Grounded Base

14. Applications of Static Electricity Reducing air pollution Cling wrap Painting cars 14

15. Grounding Grounding strap for a car Lightning Rods Why is it dangerous if fuel trucks and airplanes are NOT grounded before pumping fuel??? 15 A spark caused by a buildup of static charge could cause an explosion

16. Grounding 16 Third rounded prong Connects to ground The function of the third, rounded prong is to protect against electric shocks and fires by connecting to the grounding wire More common with metal appliances

17. Lightning 17 Inter-cloud Lightning Cloud to Ground Lightning Intra-cloud Lightning Where is the safest place to be in a lightning storm?

18. 18 Benjamin Franklin Kite Wet hemp string Iron Key Dry silk string Leyden jar