1. Tennessee SPI Objective: Essential Question(s)
Magnetic Fields
Notes
Science
Tennessee SPI Objective:
Distinguish among the Earth’s magnetic field and the fields that surround a (permanent) magnet and an electromagnet.
Essential Question(s)
What is a magnetic field?
What are the similarities and differences between the
Earth’s magnetic field and the fields from permanent magnets?
What makes a magnet?

2. See Holt Online: Ch. 16: Sect 1 Visual Concept Title: Magnetic Fields
SPI 0807:12.3
Magnetic Fields
Notes
Science
Magnetic Fields
An invisible magnetic field exists around all magnets.
See Holt Online: Ch. 16: Sect 1 Visual Concept
Title: Magnetic Fields N S

3. Notes Science SPI 0807:12.3 Magnetic Fields Magnetic Fields
You can see the magnetic field lines by using fine iron filings.
Note: - the field lines are concentrated at the ends (called poles)
South Pole
North Pole

4. F.Y.I: Why Are Some Substances Magnetic?
SPI 0807:12.2
Electromagnets
Notes
Science
F.Y.I: Why Are Some Substances Magnetic?
All atoms have magnetic fields with north and south poles
Atoms in objects are found in areas called domains.
If the north and south poles in a domain line up, this makes the object magnetic.
If they don’t line up, the object is not magnetic.

5. See Holt Online Ch. 16: Sect 1 Visual Concept
SPI 0807:12.3
Magnetic Fields
Notes
Science
Magnetic Poles: North and South
are areas on a magnet that have opposite magnetic qualities.
One area is called the north pole.
The opposite area is called the south pole.
F.Y.I.-the field lines start at the north pole & end at the south pole
See Holt Online Ch. 16: Sect 1 Visual Concept
Title: Magnetic Poles
South Pole
North Pole

6. Notes Science SPI 0807:12.3 Magnetic Fields North and South Poles
All magnets have these poles regardless of their shape
Also, if you cut a magnet in half, each half will still have these two poles (north and south)
Bar magnet
Horseshoe Magnet
Donut magnet

7. Notes Science SPI 0807:12.3 Magnetic Fields Magnetic Forces
magnets exert force on other magnets
“Opposites attract”
(North & South pull towards each other) N S
“Like repels”
(North & North or South & South push away) N S

8. Notes Science SPI 0807:12.3 Magnetic Fields Earth is a Giant Magnet
Earth has a powerful magnetic field called the geomagnetic field
See Holt Online: Ch. 16: Sect 1 Visual Concept
Title: "Earth's Magnetic Field"
This magnetic field comes from moving iron particles inside magma deep in the planet’s core

9. Magnetic poles and geographic poles are not the same!
SPI 0807:12.3
Magnetic Fields
Notes
Science
Magnetic poles and geographic poles are not the same!
Earth's north magnetic pole is geographically south (Antarctica)
Earth's south magnetic pole is geographically north (Artic)
Geographic North
Geographic South
Geographic North
Magnetic North
Magnetic South
Geographic South

10. Notes Science SPI 0807:12.3 Magnetic Fields Magnetic South Pole
Magnetic North Pole

11. Notes Science SPI 0807:12.3 Magnetic Fields
Another name for Earth's magnetic field is the magnetosphere.
Notes
Science
The magnetosphere protects us from harmful solar radiation

12. Notes Science SPI 0807:12.3 Magnetic Fields
We can see the solar wind hitting Earth's magnetosphere.
In the northern hemisphere this is called the Aurora Borealis.
In the southern hemisphere this is called the Aurora Australis
SPI 0807:12.3
Magnetic Fields
Notes
Science
View this video: Title: "Dance of the Spirits-Northern Lights
Link: Northern Ligths Video Clip

13. Science Questions SPI 0807:12.3 Magnetic Fields
Here is an example of a question you might see on a quiz or test.

14. Science Questions SPI 0807:12.3 Magnetic Fields
Here is an example of a question you might see on a quiz or test.

15. Science Questions SPI 0807:12.3 Magnetic Fields
Here is an example of a question you might see on a quiz or test.

16. Science Questions SPI 0807:12.3 Magnetic Fields
Here is an example of a question you might see on a quiz or test.

17. Science Questions SPI 0807:12.3 Magnetic Fields
Here is an example of a question you might see on a quiz or test.