1. CH 5 – Electricity and Magnetism

4. Magnetism Describes all phenomena caused by magnets
A magnet is an object that can attract other objects that contain iron, cobalt or nickel
How do they work? It’s… complicated
Quantum physics and electron spin and magnetic dipole moment
The short answer? Basic property of certain substances

6. Magnetism Notes
In order for a substance to be considered magnetic it must have 2 criteria:
It must have domains (north and south poles)
The domains must be aligned

7. Magnet Rules Has a north and south pole
Opposite poles attract, same poles repel
If you cut a magnet in half, each piece has a north and south pole
The more distance between two poles, the weaker the force will be (attraction or repulsion)

8. Notes
By convention, the north pole of a magnet corresponds to the end that naturally turns towards the Earth’s magnetic pole that is nearest to the Earth’s North Pole
So technically speaking… the Earth’s North pole is ‘magnetically a south pole’
Confusing…

9. Magnetic Fields
and-compass

11. Magnetic Fields
A magnetic field is the area around which the effects of a magnet are felt by another magnet
A magnetic field always travels from North to South poles and can travel in all directions as long as there is attraction or repulsion

12. Example 1

13. Example 2

14. Example 3

15. Example 4

16. Example 5

18. Magnetic Shield

20. Earth’s Magnetic Field
Inside the Earth’s surface there is a huge amount of ferromagnetic liquids. These liquids are constantly in motion around a solid iron core and produce a massive magnetic field which can be felt anywhere around the world

22. Poles Reversing
magnetic-field-flip-could-happen-sooner-than-expected/

24. Magnetic Field of a Live Wire
Electrons flowing through a wire generates a magnetic field
Right Hand Rule
Gives us current direction (which way the electrons are flowing) and magnetic field direction
Thumb: points to current direction (-) (electrons / electricity flows from + to -)
Fingers: curl in the magnetic field direction (N to S)
Fingertips are like the N part of the compass

25. Thumb: points to current direction (-) (electrons / electricity flows from + to -)
Fingers: curl in the magnetic field direction (N to S)

27. Arrow Notation
Thumb Points Away From Paper
Thumb Points Into Paper

31. Ferrofluid