1. Magnetism
Khan video Magnetism

2. What causes a compass to behave as it does?
Earth’s gravity
Earth’s shape
Earth’s geographic north pole
Earth’s magnetic field
Magnetic poles that are alike
attract each other
repel each other
do not interact
have the same shape
As in the case of unlike magnetic poles, unlike electric charges
exist in pairs
Earth’s magnetic field…causes a compass to behave as it does
Magnetic poles that are alike…repel each other
Unlike electric charges...attract each other

3. History of Magnetism 2000+ years ago 1000 years ago
Greeks near the city of Magnesia found strange and rare stones with the power to attract iron—called them magnetite (Fe3O4)
Lodestone- naturally magnetized piece of magnetite
1000 years ago
Chinese stroked a steel needle with “lodestone” (‘lode’ means to lead or to attract) and it became "magnetic" as well.
When freely suspended, it pointed north-south. The magnetic compass soon spread to Europe. 

4. Christopher Columbus- 1492
Used a compass when he crossed the Atlantic ocean
His observations:
the compass needle strayed slightly from exact north
as indicated by the stars
the variation changed during the voyage

5. But, they did not understand how it worked!
What’s happening?
Basically, people knew the magnetism existed, and learned useful applications for it.
But, they did not understand how it worked!
500 years ago
William Gilbert, physician to Queen Elizabeth I of England, proposed an explanation:
“The Earth itself is a giant magnet, with its magnetic poles some distance away from its geographic poles”
Geographic poles- the points defining the axis around which the Earth turns

6. Safety with Magnets Magnets should not be held near these things:
Credit cards
Magnetic I.D. cards
TV or VCR
Computer monitor
Floppy computer discs
Cassette Tapes/ Video Tapes
Tape Recorders
Radio
Any Speakers
A magnet will harm most electrical devices!!!

7. Using Magnetism for Evil?!
Magneto is a powerful mutant with the ability to generate and control electromagnetic forces.
He can shape and manipulate magnetic fields that exist naturally or artificially.
Magneto has been the X-Men's most prominent enemy ever since his first appearance.

8. Magnetic Force
Magnetism is a physical property of a substance; the force of attraction or repulsion of magnetic materials
Force is stronger than gravitational force (allows us to pick up objects using a magnet )
Magnetic fields (half way down the page):
Can be mapped
More field lines indicates the strength of the magnet in that area
Strongest near the poles 
Stronger closer to the magnet than further away.

9. Properties of Magnets S N S N S N S N
All magnets have two opposite poles.
No matter how small or broken, each piece will have its own positive and negative pole. 
There are no unpaired poles.  Poles have been labeled as north and south.
A magnet is capable of producing an electric current.
When poles get near each other, they exert magnetic forces on each other
Magnetic poles that are alike repel each other.
Magnetic poles that are different attract each other. S N S N S N

10. The flow of electrons that creates an electric current.
Electricity
The flow of electrons that creates an electric current.

11. Attraction for iron associated with electric currents
Magnetism
Attraction for iron associated with electric currents

12. Comparing Electricity & Magnetism
+ and – Charges
North and South Poles
Like Charges Repel
(-,- & +,+)
Like Poles Repel
(N,N & S,S)
Unlike Charges Attract
(+,- & -,+)
Unlike Poles Attract
(N,S & S,N)
electric field lines flow from - to +
magnetic field lines flow N to S

13. Double Bubble Magnetism vs. Electricity

14. Double Bubble Magnetism vs. Electricity
Magnets are needed
for electricity
Opposites
Attract &
Like Repel
Electricity
Magnetism
Electromagnetism
Fields

15. Double Bubble Magnetism vs. Electricity
Magnets are needed
for electricity
+ and –
Charges
North & South
Poles
Permanent &
Temporary
Magnets
Static &
Current Electricity
Opposites
Attract &
Like Repel
Magnetism
Electricity
Alternating &
Direct Current
Bar, Doughnut,
& Horseshoe
Magnets
Electromagnetism
Divided further
according to
composition
Series &
Parallel
Circuits
Fields

16. Double Bubble Magnetism vs. Electricity
Opposites
Attract &
Like Repel
Magnetism
Electricity
Electromagnetism

17. Magnetism
Paramagnetism - When a paramagnetic material is placed near a magnet, it will be attracted to the region of greater magnetic field
Exhibited by: materials containing transition elements, rare earth elements and actinide elements 
Diamagnetism - When a diamagnetic material is placed near a magnet, it will be repelled from the region of greater magnetic field
Exhibited by: all common materials, but is very weak
Ex. People, frogs
Ex. Metals such as bismuth, copper, gold, silver and lead, as well as many nonmetals such as water

18. "Magnetic Man" Malaysia, Liew Thow Lin, 70 years old
Has the ability to make metal objects stick to his skin.
After reading an article about a family in Taiwan who possessed such power, he says he took several iron objects and put them on his abdomen, and to his surprise, all the objects including an iron, stuck on his skin and didn't fall down.
Pulled a car 20m along a level surface by means of an iron chain hooked to an iron plate on his midriff
Since this "gift'' is also present in three of his sons and two grandchildren, he figures it's hereditary.

19. The boy with the magnetic personality
May 11, 2011
Six-year-old Croatian, Ivan Stoiljkovic, can stick metal objects to his body such as: spoons, mobile phones and even frying pans
Reality: Doctors say he's ability is related to suction properties in his skin and not to magnetic force but anyway what he can do is very impressive.

20. 3 Types of Magnets
Natural (Permanent) Magnet- A magnet that retains its magnetization after removal from a magnetic field.
Can occur naturally.
Lodestone is a natural permanent magnet.
Can produce forces at all times
Earth produces a magnetic field due to molten iron in core and spinning of the earth
Permanent magnets can be damaged from extreme heat and dropping

21. Permanent Magnets
Each atom in a ferromagnetic material like iron is like a little magnet.
These magnets are all aligned in tiny regions called “domains”.
At high temps these “domains” can align in the presence of an external field (like Earth’s) leaving a permanent magnet.
Lets melt the iron, and bring in a magnetic field.
Temp
Now, when we let the solid cool down, and take away the external magnetic field, we have formed a permanent magnet in the same direction as external field.
Melting point
Domains
Bar Magnet

22. 3 types of magnets
2. Temporary Magnet- only have magnetic properties for a short period of time, after exposure to a permanent magnet
Iron—composed of molecules (domains)
All different directions = no magnetic force or pull
All lined up in one direction = force to pull things towards them

23. Groups of atoms join so that their magnetic fields are all going in the same direction These areas of atoms are called “domains”
An unmagnetized substance looks like:
While a magnetized substance looks like:

24. 1. Impact (hit it) 2. Heat it 3. Electricity
How to demagnetize a magnet:
1. Impact (hit it)
2. Heat it
3. Electricity
This causes the domains to become random again!

25. 3 types of Magnets
3. Electromagnet- temporary magnet, made by coiling wire around a piece of soft iron.
When an electric current is passed through the wire, a magnetic field is produced.
The field magnetizes the iron core by aligning domains within the iron.

26. S N S N S N Attract  Attract  Repel 
What happens if a magnet breaks in half?
One half has a north pole only, and one half has a south pole only
Neither half will have a pole
Each half will be a new magnet, with both a north and south pole
Neither half will attract or repel.
Draw arrows to show if the cars attract or repel each other. On the space to the right, write the word that describes the action of the cars (attract or repel).
The region around a magnet where the magnetic force is exerted is known as its
magnetic pole
magnetic field
magnetic domain
Magnetism can be considered a
nuclear property
physical property
chemical property
A temporary magnet
keeps its magnetism for a long time
cannot be destroyed
easily loses its magnetism S N S N S N
Attract 
Attract 
Repel 

27. What on Earth is a Cow Magnet?
Magnets come in many shapes and sizes, but the cow magnet was invented to solve a very serious problem of dairy farmers.
When the cow grazes, it often consumes and swallows small pieces of iron: baling and barbed wire, staples, nails, and other metallic objects.
These objects are indigestible and lodge in the reticulum and cause inflammation.
This results in lower milk production (for dairy cattle) or lower weight gain (for feeder stock).
This condition is called hardware disease.
Solution: A rancher/ farmer feeds a magnet to each calf at branding time; the magnet settles in the rumen or reticulum and remains there for the life of the animal.
The cow magnet attracts such objects and prevents them from becoming lodged in the animal's tissue. While the resultant mass of iron remains in the cow's rumen as a sort of bezoar, it does not cause the severe problems of hardware disease.
One small cow magnet can help a cow for her whole life!

28. Magnetic Fields Procedure:
Place a magnet into a tray, put a piece of paper over the magnet.
Lightly sprinkle iron filings on and around the magnet, gently tap the paper.
Observe the formation around the magnets, and sketch what you see.
Types of Demonstration:
One magnet
Two magnets- Attracting
Two magnets- Repelling

29. Mapping Magnetic Fields
One Magnet
Two Magnets- Attracting
Two Magnets- Repelling N S N S N S
Draw on lab N S S N

30. MAGNETIC FIELDS- One Magnet
This picture demonstrates what occurs when one magnet is placed on paper, and iron filings are sprinkled around it.

31. MAGNETIC FIELDS- Two Magnets Attracting
This picture has two magnets placed on a piece of paper with their opposite poles facing each other, and iron filings are sprinkled around them.

32. MAGNETIC FIELDS- Two Magnets Repelling
Pictured here are two magnets placed on a piece of paper with their like poles facing each other, and iron filings are sprinkled around them.
On lab

33. Like poles repel…
Opposite poles attract!

34. The Earth’s magnetic field extends far into space
The Earth’s magnetic field extends far into space. It is called the “magnetosphere.”
When the magnetic particles from the sun, called “solar wind”, strike this magnetosphere, we see a phenomenon called…

35. The Aurora Borealis in the Northern HemisphereAnd the Aurora Australis in the Southern Hemisphere

36. Magnetic force is strongest at the poles.
True / False. You can see magnetic fields without assistance.
By looking at magnetic field patterns, you can tell where the magnetic forces are the strongest. Where are you looking and what do you see?
You can tell by these lines whether the magnets are (A) attracting, or (B) repelling. What would each look like??—sketch and describe.
False. Magnetic fields are invisible (until you use iron filings to help map them!).
Magnetic force is strongest at the poles.
Where all of the lines converge/intersect
Where the lines are most concentrated
(A) Attracting- lots of lines connecting between them
(B) Repelling- lines do not interact or touch—nothing observed between the magnets

37. Electricity/Magnetism Videos

38. Electricity Notes

39. A. Intro All matter is composed of atoms.
Atoms are made up of smaller particles called protons, neutrons, and electrons.
Protons are positively charged and electrons are negatively charged.
According to the law of electric charges, like charges repel and opposite charges attract.
If an atom loses electrons it becomes positively charged. If an atom gains electrons it becomes negatively charged.

40. There are three ways to “charge” an object...
1. Conduction– e- are transferred by direct contact
Ex) uncharged metal & + charged glass rod
(e- travel from metal to glass rod leaving the metal + charged)
2. Induction- when charges in an uncharged object are rearranged w/o direct contact
Ex) – charged balloon and neutral wall
(+ charged object near a neutral object and e- in neutral object are attracted to + charged object & move towards it)
3. Friction- when two objects are rubbed together electrons are “wiped” from one to another
Ex) rub a plastic ruler with a cloth
(e- are transferred from the cloth to the ruler)

41. Charge can be detected by using an Electroscope.
Ex) Glass flask with a metal rod inserted through a rubber stopper.
There are two metals leaves at the bottom of the rod.
Leaves hang straight down when not charged and move apart when charged.
Uncharged Charged

42. Static Electricity Static – not moving
Static electricity is the build up of charges on an object.
The charges that create static electricity do not move away from the object they are stuck to.

44. Why do clothes stick together after they are taken out of the dryer?
When you dry clothes in the dryer, different fabrics rub together, and electrons from a cotton sock (for instance) may rub off onto a polyester shirt. That's why clothes sometimes stick together and make sparks when you pull them apart.

45. How does a fabric softener (dryer sheet) work to prevent static cling?
As these sheets bounce around with your clothes, they add a uniform antistatic coating to the fabric. Rather than cotton rubbing against polyester, you've got the antistatic coating on the cotton rubbing against the antistatic coating on the polyester. No electrons rub off and you don't get any static cling.

46. The loss of static electricity is discharge.
Gradually, over time, charges that build up on an object leave the object.
Electric discharge may happen rapidly or slowly.
The most dramatic example of electric discharge is lightning.

47. Current Electricity
Electric current is a continuous flow of electrons.
Current is how fast charge passes at a given point.
There are 2 types of electric current: Alternating Current (AC) and Direct Current (DC).
Electric current produced by batteries is DC and electric current from your home outlet is AC.

48. Current in a wire is determined by voltage and resistance
Current in a wire is determined by voltage and resistance. The higher the voltage, the more energy is released.
Resistance is the opposition to the flow of electric charge.
It is represented with the symbol Ω .
The higher the resistance, the less current is in it.
Resistance can change depending on an object’s material, thickness, length, and temperature.

49. An example of a material that has a low resistance is copper.
Iron is a good conductor.
Materials with a low resistance are used to make wires.
A thick pipe has less resistance because there are more spaces for current to travel through.
A thin pipe has more resistance because it does not have to move around many spaces.

50. In general, resistance increases as the temperature of a metal increases.
This happens because atoms move faster at higher temperatures and get in the way of electric charge.
If you cool certain materials, resistance will drop to zero.
These materials are known as superconductors.
They can be useful because very little energy is wasted when current travels through them.

51. Where to find the Vocabulary Words:
Sciencesaurus
Insulator
p. 317
Conductor
p. 317 & 477
Static Electricity
p. 316 & 516
Current Electricity
p. 317 & 479
Alternating Current
p. 317 & 468
Direct Current
p. 317 & 481
Circuit
p. 318 & 475
Circuit Symbols
* Glue or Tape * to each corresponding index card
Open Circuit
p. 318
Closed Circuit
Series Circuit
p. 319 & 514
Parallel Circuit
p. 319 & 505

52. Circuit Diagram

53. Open Circuit
The absence of flow of electrons through a circuit because of an opening in the circuit.
Ex) Lights Off

54. Closed Circuit
An electric current providing an uninterrupted, endless path for the flow of electrons.
Ex) Lights On

55. Series Circuit A circuit having one path for the electricity to flow.
If one bulb goes out, the circuit is open and they all go out!
Ex) old x-mas tree lights & fuses

56. Parallel Circuit
A circuit having MORE than one path for the electricity to flow – “branches”.
If one bulb goes out, the rest can stay on w/ their own path!
Ex) Most things in your household…
lights, appliances, etc.

57. Back – Measuring Electricity
Word
Definition
Units
Water Analogy
Pic/Symbol
Current
Voltage
Resistance
Capacitor

58. Current Voltage Resistance Capacitor Word Definition Units
Water Analogy
Pic/Symbol
Current
H20 Flow – Current
Voltage
Water Pressure- Amt of flow
Resistance
Difficulty of water flow due to Pipe Size or Dam
Capacitor
Water storage – Reservoir
- Dam

59. Limits the amount of e- current
Word
Definition
Units
Water Analogy
Pic/Symbol
Current
Flow of e-
H20 Flow – Current
Voltage
Electrical
Pressure
Water Pressure- Amt of flow
Resistance
Limits the amount of e- current
Difficulty of water flow due to Pipe Size or Dam
Capacitor
Stores
Electricity
Water storage – Reservoir
- Dam

60. Limits the amount of e- current Ohms
Word
Definition
Units
Water Analogy
Pic/Symbol
Current
Flow of e-
Amps
(Amperes)
H20 Flow – Current
Voltage
Electrical
Pressure
Volts
Water Pressure- Amt of flow
Resistance
Limits the amount of e- current
Ohms
Difficulty of water flow due to Pipe Size or Dam
Capacitor
Stores
Electricity
Farads
Water storage – Reservoir
- Dams

61. Back – Measuring Electricity
Word
Definition
Units
Water Analogy
Pic/Symbol
Current
Flow of e-
Amps
(Amperes)
H20 Flow – Current
Voltage
Electrical
Pressure
Volts
Water Pressure- Amt of flow
Resistance
Limits the amount of e- current
Ohms
Difficulty of water flow due to Pipe Size or Dam
Capacitor
Stores
Electricity
Farads
Water storage
Reservoir
Dam

62. 3 Things Needed to Create Electricity
Magnet
Conductor
Motion

63. [The Volume of the Current]
Amp
Measures
Electrical Current
[The Volume of the Current]
SI Unit = Ampere.

64. {The Force or Push of Electricity}
Volt (V)
Measures
Electrical Pressure
{The Force or Push of Electricity}
SI Unit = Volts

65. Ω Measures Electrical Resistance
Ohm Ω
Measures Electrical Resistance
{How difficult it is for the current to pass through}
SI Unit = Ohm

66. Resistance
Measures how difficult it is for electricity to pass through an object.
SI unit = Ohm Ω

67. Electrical Resistance
Low Resistance
Easy to get through
Good Conductors (copper, gold, etc)
Large/Thick Wires
High Resistance
Tough to get through
Good Insulators (glass, rubber, etc)
Small/Thin Wires

68. Plumbing Pipe Analogy Voltage/Volts (V) = Water Pressure
It determines how fast the electrons will travel through the circuit.
Current/Amps = Flow Rate
A measure of the volume of electricity that flows past a given point.
Resistance/Ohms = Pipe Size
Measures the difficulty of electric flow

69. Electrifying Electrifoldable Quiz!
Part I = 20 Matching
5 points each
100 points
Part II = Thinking Maps
10 parts x 10 points each

70. Part I: Matching
___ A material that does not allow electricity to pass through it easily
___ A circuit with more than one path for electricity to flow
___ Lightning is an example of this type of electricity
___ A type of circuit where if one bulb goes out they all go out
___ Copper, zinc, and gold are examples

71. 6. ___ A type of current electricity that flows in 1 direction
7. ___The flow of electrons that creates an electric current
8. ___ Negative charges attract…
9. ___ Measures electric current
10. ___A type of circuit where electrons are able to flow because there are no openings

72. 11. ___ Negative charges repel…
12. ___ Measures electrical pressure
13. ___ Load
14. ___ Light, wires, and a battery
15. ___ Has both north and south poles

73. 16. ___ 2 types of Current Electricity
17. ___ Motion, conductor, and a magnet
18. ___ A circuit with an opening
19. ___ Stores electricity
20. ___ Unit used to measure resistance

74. Answers S - Insulator K – Parallel Circuit D – Static Electricity
C – Series Circuit
B - Conductors
F – Direct Current
G - Electricity
H – Positive Charges
T - Amps
I – Closed Circuit
J – Negative Charges
O - Voltage
L - Light
M – 3 parts of a Circuit
E - Magnet
N – AC/DC
P – 3 things for Electricity
Q – Incomplete Circuit
R - Capacitor
A - Ohm