1. 9/3/2019
Introduction to Physical Science Monday, Wednesday, Thursday Tom Burbine

3. Magnetic Poles Like poles repel Opposite poles attract North pole
South pole

5. Magnetic Force
1) Between magnets, it is the attraction of unlike magnetic poles and the repulsion of like magnetic poles
2) Between a magnetic field and moving charge, it is the deflecting force due to the motion of the charge

6. Difference between magnetic poles and electron charges
Electric charges can be isolated
Protons and electrons can exist separately
Magnetic poles cannot
North magnetic poles can’t exist without south poles

7. If you break a magnet in half, each half will act as a magnet
If you break that piece in half, you will then have four magnets
This suggests that the atoms themselves are magnets

8. Magnetic Field
The region of magnetic influence around a magnetic pole or a moving charged particle
Field of force

9. Motion of electric charges
Electron spinning
Electron revolution around the protons

10. Electron spinning An electron spinning creates a magnetic field
A pair of electrons spinning in the same direction creates a stronger magnet
A pair of electrons spinning in the opposite direction work against each other

12. Metals
Materials such as iron, nickel, and cobalt have electrons whose spins do not cancel out
Iron has four paired electrons that can have the same spin

15. Magnetic domains
Clusters of atoms line up with one another

16. Permanent Magnet
Place a piece of iron (or a similarly magnetized material) in a strong magnetic field

17. Moving charge produces a magnetic field
A current of charge produces a magnetic field

18. Electromagnetic Induction
Electric current can be produced in a wire simply by moving a magnet into or out of a coil of wire
A voltage is induced by the relative motion between a wire and the magnetic field

20. Faraday’s Law
The induced voltage of a coil is proportional to the number of loops multiplied by the rate at which the magnetic field changes within those loops

21. More practical to move the coil then move the magnet
Generator has a rotating coil in a stationary magnetic field
Converts mechanical energy into electrical energy

23. Any Questions?