Magnets have been known and used for navigation for centuries, with the ancient Greeks using a magnetic stone called magnetite. Magnetism is the force of attraction or repulsion between magnetic materials due to the arrangement of electrons in their atoms. The Earth itself acts as a large magnet, with a magnetic field strongest at its north and south magnetic poles. Other planets and the Sun also have magnetic fields extending into space.

1. Magnetic Force Interactions of Forces and Motion Teacher Page

2. Magnets have been known for centuries. The Chinese and Greeks knew about the “magical” properties of magnets. The ancient Greeks used a stone substance called “magnetite.” They discovered that the stone always pointed in the same direction. Later, stones of magnetite called “lodestones” were used in navigation.

3. What is Magnetism? Magnetism is the force of attraction or repulsion of a magnetic material due to the arrangement of its atoms, particularly its electrons .

4. Will these items be attracted to a magnet? yes no yes no yes no yes no yes no yes no Click next screen for answers.

5. N S Were you correct? Why were these things attracted to the magnet?

6. S N S N S N S N What will happen when the ends of the two bar magnets are placed close together? What will happen when the ends of the two bar magnets are placed close together? Answers next

7. N N S S S N S N The N orth and S outh poles of the magnet are attracted to one another. Like poles of the magnet are not attracted, or repel one another.

8. If you cut a magnet in half, you get 2 magnets!

9. An unmagnetized substance looks like this…

10. While a magnetized substance looks like this…

11. How to break a magnet: 1. Drop it 2. Heat it This causes the domains to become random again!

12. N S N S N S N S These magnets are attracted to one another. Draw these magnets and label their poles? Explain your drawing. Click for answer

13. William Gilbert, an English physician, first proposed in 1600 that the earth itself is a magnet, and he predicted that the Earth would be found to have magnetic poles.

14. The Earth is a magnet: Magnetic South Pole Magnetic North Pole It exerts magnetic forces and is surrounded by a magnetic field that is strongest near the North and South magnetic poles Geographic North Pole Geographic South Pole

15. The sun has a magnetic field, too. It extends far above the sun’s surface. Other planets in the solar system also have these magnetic fields

16. 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…

17. The Aurora Borealis in the Northern Hemisphere And the Aurora Australis in the Southern Hemisphere