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?

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

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

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.

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

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

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

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

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

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

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

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

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

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

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

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

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