1. ELECTRICITY

2. Notes vs Discussion In this chapter we will write out our class notes
Your are to write any information that is in RED
Anything in black does not need to be copied by you.
Your outline will only consist of practice worksheets and lab activities for this chapter.

3. Atom ATOMIC
BOMB
Nucleus NUCLEAR
POWER
Electron Electricity .

4. The ATOM The atom is made of 3 basic parts: Electrons 1. Protons
2. Neutrons
3. Electrons
Electrons
(Negatively charged)
Nucleus
Neutrons
(Neutral)
Protons
(Positively charged)

5. HYDROGEN
(Proton)

6. Nucleus
Protons
Neutrons

7. NUCLEUS + ELECTRONS = ATOM

8. # PROTONS = # ELECTRONS
Neutral

9. # PROTONS > # ELECTRONS
Missing Electron
Positive

10. # PROTONS < # ELECTRONS
Negative
Extra Electron

11. Electric charge 2 Types Pos charge - more protons than electrons
Neg charge - more electrons than protons
Neutral - same amount of protons and electrons

12. Atoms become “charged” when they gain or lose electrons
Gain electrons = become - charged
Lose electrons = become + charged
Protons do not move from atom to atom.
The natural state of any atom is to be neutral.
If an atom becomes “charged” we call it an Ion.

13. Different charges attract
Law of Electrical Charges
Different charges attract
Same charges repel
Demo

14. Another way to show attract and repel
The act of repelling or attracting occurs because of
Electric Forces

15. Electroscope – A device used to
detect a static electrical charge.

17. Why does your hair do this??
Static Electricity - The build up, or collection of negative charges on an object causing an electric field around that object.
Why does your hair do this??
Each hair becomes negatively charge and therefore REPELS each other.

18. Electric Discharge -The rapid movement of excess charge from one place to another.
Sparks (Small discharge)
Lightning bolts (Large discharge, millions of volts)

19. 3 ways lightning can strike
Lightning - a large electrical discharge between the atmosphere and ground.
3 ways lightning can strike
Cloud to ground
Ground to cloud
Cloud to cloud

20. Formation of Lightning
Collection of negative charges in cloud.
Ground becomes positive.
Stepped leader forms in between and makes connection with ground
Invisible discharge takes place
Return stroke that we see.
4 – 6 return strokes can take place during one strike.

21. Positively charged at the top
Positively charged at the top
___ ___Negatively charged towards bottom ___ ___ ___ ___ ___ ___ ___ __ __ __ __ __ __ __
Stepped Leader forms first
The lightning we see “return stroke”
Positively charged ground

22. Invisible Channel is very jagged and unpredictable.

23. Types of Lightning
Ribbon lightning

24. Ball Lightning

25. Sheet Lightning

26. Bead Lightning

27. Red Sprites

28. Blue jets

29. Lightning and Thunder 1mile every 5 seconds

30. Electric Circuits Electric current The “flow of electrons” is called
Circuit – A closed conducting pathway for electrons to flow through.
The “flow of electrons” is called
Electric current
Electric current is a lot like the flow of water through pipes
Simulation

31. Simple Circuits 3 parts to a simple Circuit 1. Source of Electricity
“battery”
2. Conductor
“wire”
3. Load
“Light bulb or motor”
What electrons do work on

32. Simple Circuit
Source + _
Conductor
Load

33. Simple Circuit
Source + _
Conductor
Load

34. Batteries and Bulbs “Student Challenge!!!!!!”
Can you and your partner work together to make the light bulb light up!!!! Use only the battery, bulb (with no socket, and a piece of wire. There are ten different combinations. Try to figure out all ten. You must make a drawing of how you arrange the items to make the bulb light using the symbols below. Good Luck!!!

35. Clue # 1
Touch here
Touch here

36. Clue #2

37. Clue #3

38. Conductors (very low resistance)
Materials allow electrons to flow easily.
Used in electrical circuits.
silver
copper
gold
aluminum
iron
steel
brass
bronze
mercury

39. Insulators (very high resistance)
Don't allow electrons to flow easily.
Used to protect ourselves.
glass
rubber
asphalt
fiberglass
cotton
paper
wood
plastic
air

40. Resistors (known as a semi-conductor)
Allow a small amount of electrons to pass through. Much less than a conductor. Becomes hot due to friction. This heat is USEFUL!
Graphite
Carbon
Tungsten
Silicon
Nickel

41. The Incandescent light bulb

42. Argon gas

43. Tungsten Filament is double coiled to allow for up to 2 feet of wire give off the glow.

44. 2 types of batteries Source of Electricity (Battery) Dry Cell
Supplies electrical potential energy to a circuit.
Sets the voltage of the circuit.
2 types of batteries
Dry Cell
Wet Cell

47. Wet Cell versus Dry Cell
Used in automobiles
High voltage (12v)
Short life
Needs recharged often
Liquid electrolyte (salt or acid)
Lead plates
Used in small electronic equip.
Low voltage ( 1.5v)
Long life
Carbon center +
Zinc outer case -
Manganese paste electrolyte

48. Electrical Symbols Source Voltmeter Light bulb Ammeter Motor
Switch on
Switch off
Voltmeter
Ammeter
Resistance
Fuse

49. Series Circuits – a circuit that has only a single path (one loop) for current to flow through all of its parts.
Bulbs in Series

50. Batteries in Series

51. Parallel Circuits - requires more than one path for current flow in order to reach all of the circuit parts.

52. Batteries in Parallel

53. Ohm’s Law
The relationship between the voltage, amperage, and resistance in an electric circuit.

54. Voltage
The amount of electrical potential energy given to circuit.
Voltage=
“The pressure or push on electrons”
Measured in
Volts
Symbol = V
Voltage = Amperage x Resistance
V = I x R
Formula
220 volts = 11 amps x 20 ohms

55. Resistance
How difficult it is for electrons to travel through a material
Resistance=
“The friction from electrons, produces light and heat”
Measured in
ohms
Symbol =
Resistance = Voltage / Amperage
R = V / I
Formula
30 ohms = 90 volts / 3 amps

56. Amperage
The amount of current that passes a given point in one second.
Amperage=
“The flow of electrons”
Measured in Amps
Symbol = I
Amperage = Voltage / Resistance
I = V / R
Formula
6 amps = 12 volts / 2 ohms

57. Alternating Current
Electric current that travels back and forth in a circuit.
Changes direction 60 times in a second!!!
Much more intense than Direct Current
Created by a generator (magnets inside)
Can travel great distances

58. Direct Current Electric current that travels only in one direction.
Produced by chemical reactions (batteries)
Low intensity

59. Voltage
Amperage
Resistance

60. Fuses and Circuit Breakers
Devices that open a circuit due to overload. (drawing too much current)
* prevents damage or potential fire
Fuses – open a circuit when a narrow filament melts. Not reusable.

62. New Fuse
Blown Fuse

63. Breakers – a switch that automatically opens a circuit when overload occurs. Reusable
Switch can be opened 3 different ways.
1. heat from circuit causes bimetallic strip to separate 2 metals.
2. electromagnet breaks circuit
3. small explosion

65. Calculating Electrical Cost
Step 1 – Calculate wattage (volts X amps)
220 volts X 3 amps = 660 watts
Step 2 – Convert watts to Kilowatts (X .001) or divide by 1000
660 X .001 = .66 kilowatts
Step 3 – Multiply kilowatts by the amount of time used. All numbers must be in hours.
.66 kilowatts X 3 hours = 1.98 Kilowatt - hours
Step 4 – Multiply Kilowatt – hours by the rate or price (around $0.10)
1.98 X .10 = $0.19

66. Power
- the rate at which a device converts electricity into another form of energy.
Answer labeled as Watts
Electric oven - electricity into heat
Motors - electricity into motion
Toaster – electricity into heat
Hair dryer – electricity into heat and motion