1. Bell Ringer: You need a calculator, ipad, book & periodic/reference table!
1) Which way do electrons flow in a circuit?
2) Do like charges attract or repel each other?
3) Name two types of forces that we have talked about in this class, and describe them.
Quick Math Review:
Put these numbers in scientific notation:
14,340,
Put these numbers in standard notation:
1.23 x x 10-3

2. Magnetism
Chapter 21

3. Magnets Magnetism Force of attraction/repulsion between two objects.
2 sides to every magnet:
North (N)
Points magnetic north
South (S)
Points magnetic south
end

4. Magnets Magnetic Forces Opposites Attract
Closer to the Pole = Stronger Force
Area it acts on objects is called the Magnetic Field
end

5. Magnets Field Lines show the area affected by the Magnetic Field
Arrows go from North to South
More Lines = Stronger Field
When 2 Magnets come close together the Field Lines interact with each other!
end

6. Magnets
Field Lines interact between 2 magnets
Attraction
end

7. Magnets
Repulsion
end

8. Magnets Magnetic Domain Area where atoms have the same magnetic charge
Point in the same direction
Create a magnet using Magnetic Induction
Force all Domains to point in the same direction
end

9. Magnets Magnets can be either: Temporary Permanent
Easily magnetized but loses strength quickly.
Permanent
Hard to magnetize but keeps strength a long time.
Common Magnetic Elements
cobalt, nickel, iron, aluminum
end

10. Electromagnets
As Electricity runs through a coiled wire it creates a Magnetic Field
Magnetic Field lines look the same as Field Lines
Known as an Electromagnet
end

11. Electromagnets
Electromagnets all us to use electricity to create magnets of strength & to make objects attract
end

12. Electromagnets 3 parts: 1. Power Source 2. Wire 3. The Core
Wire wrapped around the core
Core
3 parts:
1. Power Source
Need to be able to change the Current in the circuit
2. Wire
3. The Core
end

13. Electromagnets To increase the strength of an electromagnet:
Increase the current
Increasing the number of turns in the wire
Wrap the wire more times around the core
Use a core that is easily magnetized
end