WHAT IS ELECTRICITY

1. WHAT IS ELECTRICITY?

2. ATOMIC PARTS Electron = negative, easily lost Proton = positive Neutron = no charge, neutral

3. Opposite charges attract

4. Types of Materials Conductors � materials that allow electrons to flow through (metals, copper wire, water) Insulators � materials that do not allow electrons to pass through (wood, glass, plastic, rubber) Grounding- it is the process of removing the excess charge of an object by transferring (by way of a conductor) the electrons to another object. A 'ground' is an infinite source or sink for charge.

5. STATIC ELECTRICITY The build up of electrons on the surface of an object Separated charge Net charge Electrons jump Less orderly Cannot harness

6. STATIC ENERGY Rubbing a balloon on a wool sweater�creates charges on the surfaces The balloon attracts electrons from sweater

7. GAINING OF ELECTRONS O

8. STATIC ELECTRICITY

10. Why hair stands up Hair is full of electrons. Like charges repel causing the hair to stand on end The hair stands push away from each other

11. STATIC ELECTRICITY

12. Opposites attract The door knob is positively charged A person is negatively charged The electrons jump through the air in the path of least resistance creating a spark What is the crackling sound you hear when you take clothes out of a dryer?

13. Static cling In dry conditions materials cling to each other or are attracted to each other due to the law of opposites. Clothes attach to your body Clothes from the dryer have static cling due to the rubbing together. The materials in dryer sheets remove the cling. Why isn�t static cling present in humid conditions?

14. Water Conductor Water is a conductor, and so all the electrons are attracted to it. Water pulls away the extra electrons and removes the static force that is causing your clothes to cling together

15. Static in Radio & TV�s Dust and water vapor in the atmosphere create static Sensitive tuners

16. VAN DE GRAAFFGENERATOR

17. BIG SPARKS - LIGHTNING

18. Opposites attract Electrons travel from earth to positive atmosphere where the clouds pick up and store lost electrons Clouds become negatively charged as ice crystals inside the cloud rub against each other The earth or ground is more positively charged and the electrons jump from the clouds to the ground or from one cloud to another

19. Thunder Thunder is hot air colliding with cool air A lightning strike can heat the air in a fraction of a second. When air is heated that quickly, it expands violently and then contracts, like an explosion that happens in the blink of an eye. It's that explosion of air that creates sound waves, which we hear and call thunder.�

20. Lightning Rods The rod connects to a huge piece of copper or aluminum wire. The wire is connected to a conductive grid buried in the ground nearby. If lightning strikes, the system attempts to carry the harmful electrical current away from the structure and safely to ground without causing any heat damage.

21. CURRENT ELECTRICITY The flow of electrons through a conductor Charge flow Electric current Electrons flow not jump More orderly Can harness Two kinds � AC or DC Alternating or Direct Current

22. Electricity

23. DC or Direct Current Electrons flow in one direction Stored Electricity Chemical energy

24. ELECTRON SHELLS

25. A Battery has� A CATHODE which tends to accept electrons to be more stable An ANODE which tends to give up electrons to be more stable An ELECTROLYTE PASTE which transfers most of the electrons back to the anode when a circuit is complete.

26. CIRCUIT A conductor which connects a pathway between the (+) and the anode (-)

27. Battery is a charge pump Charges in battery want to get together to balance out A potential difference makes them move The paste moves the charges it does not make them The electrons will flow from negative end to the positive end

28. WET CELL BATTERY

29. DRY CELL BATTERY

30. Transfer of chemical energy to electrical & heat energy

31. MERCURY BATTERY wikipedia.org

32. POTATO BATTERY

33. Car Battery are known as "constant voltage" devices because when you put a load on them, the voltage remains the same. A good example is your car battery. A fully charged car battery will produce about 12.75 volts. If you turn on your headlights and then check your battery voltage, you will see that it remains relatively unchanged (providing your battery is healthy). At the same time, the current will vary with the load. For example, your headlights may require 10 amps, but your windshield wipers may only require 4 amps. Regardless of which one you turn on, the voltage will remain the same. because when you put a load on them, the voltage remains the same. A good example is your car battery. A fully charged car battery will produce about 12.75 volts. If you turn on your headlights and then check your battery voltage, you will see that it remains relatively unchanged (providing your battery is healthy). At the same time, the current will vary with the load. For example, your headlights may require 10 amps, but your windshield wipers may only require 4 amps. Regardless of which one you turn on, the voltage will remain the same. because when you put a load on them, the voltage remains the same. A good example is your car battery. A fully charged car battery will produce about 12.75 volts. If you turn on your headlights and then check your battery voltage, you will see that it remains relatively unchanged (providing your battery is healthy). At the same time, the current will vary with the load. For example, your headlights may require 10 amps, but your windshield wipers may only require 4 amps. Regardless of which one you turn on, the voltage will remain the same. because when you put a load on them, the voltage remains the same. A good example is your car battery. A fully charged car battery will produce about 12.75 volts. If you turn on your headlights and then check your battery voltage, you will see that it remains relatively unchanged (providing your battery is healthy). At the same time, the current will vary with the load. For example, your headlights may require 10 amps, but your windshield wipers may only require 4 amps. Regardless of which one you turn on, the voltage will remain the same.

34. CURRENT ELECTRICITY The flow of electrons or current through a circuit is constantly switching back and forth (ie. 60 times each second) When current flow is controlled it can be used to do useful work. Can be transformed into Mechanical, Heat, Radiant or Light Energy

35. Volts Voltage = Force of electrons Voltage is potential difference of electrons in 2 places Garden Hose Homes use 110v and dryer and stove uses 220v Potential Difference � needed in order for an electrical field to flow thru a material changing magnetic field creates current current = charges are moving

36. Amps Amperes - are used to measure this flow of electrons Amps = number of electrons to flow thru wire in a second 6.25 x 1018 or 6,250,000,000,000,000,000 electrons/second

37. DIFFERENT TYPES OF WIRING

38. PARALLEL AND SERIES

39. Watts- measurement of electrical power Power =work/time or volts x current (amps) Clock 3 watts Hair Dryer 1000 watts Clothes Dryer 4000 watts Kilowatt = 1 thousand watts (homes) Megawatt = 1 million watts (power plant) Gigawatt = 1 billion watts (large power plant) Quad = 1 Quadrillion BTU�s USA 74 quads/yr San Francisco 1 quad/yr BTU= Measure of energy, Amount of heat that will raise the temperature of one pound of water one degree Fahrenheit

40. Cost of electricity Energy = power x time 1kWh = 10 100 watt light bulbs burning for 1 hour Average family uses 1000kWh in 1 month Utility company charge .10/kWh = 1000 x .10 = $100.00

41. GALVANOMETER A device that detects the flow of electricity

42. Efficiency Due to 2nd law of thermodynamics Efficiency is not 100% For example if efficiency is 33% that means for every 3 parts of fuel 2 parts are waste or unusable, only 1 part is usable

43. ELECTRICITY