1. Aim: How do explain magnetic fields?

2. Do Now: How are we able to stack cars up in a pile in a junkyard?

3. The Crane uses magnetism

4. What is magnetism?

5. Magnets
A magnet has a north pole and a south pole.

6. Magnetic Rules of Attraction and Repulsion
Like poles repel. Opposite poles attract.

7. Magnetic Monopoles
A magnetic monopole has never been discovered.

8. Permanent Magnets and Temporary Magnets

9. Magnetic or Non-magnetic
Determine whether the following materials are magnetic or non-magnetic:
Paper clip
Straw
Soda Can
Cereal
Dollar bill
Iron nail
Staple
Ruler

10. Label the Poles of each magnet

11. Compass
A compass is a tiny magnet. Since the earth is a magnet, south pole of the compass needle always points toward the north pole of the Earth.

12. Compass

13. Magnetic Fields
All magnets produce magnetic fields. To find the direction of the magnetic field at a point, we can place a compass at that point. The direction of the magnetic field is equivalent to the direction in which the north pole of the compass needle points.

14. Magnetic Field = B

15. Magnetic Field
Magnetic field lines begin on the north pole. Magnetic field lines terminate on the south pole. Field lines cannot cross

16. Earth’s Magnetic Field
Why does the Earth’s magnetic field look like this?

17. Applications of Magnetic Fields
MRI
Burglar Systems
Bird Navigation
Aurora Borealis

18. Aurora Borealis

19. Magnetic Field of a Bar Magnet (Around the Magnet)

20. Magnetic Field lines can be drawn inside bar magnet

21. Horseshoe Magnet

22. Magnetic Field Lines Between Opposite Poles

23. Magnetic Field Lines Between Like Poles

24. Magnetic Field Lines Around a Bar Magnet