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19 Cards in this Set
- Front
- Back
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Magnets |
Like poles repel Opposite poles attract |
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Magnets.... |
Attract Iron |
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Lodestones: |
Natural magnets |
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Domains: |
Can break up with heat or violence |
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Soft iron: |
Has domains, but usually they aren't ordered |
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Compasses: |
Easy to pivot magnet that aligns with the Earth |
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How to make a compass: |
Magnet, needle, cork |
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Force on moving charges.... |
are perpendicular to both magnetic field and direction of motion |
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If a charged particle moves from the bottom of the board to the the top, and the magnetic field is coming out of the board, the force is in the... |
Left-right direction |
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Force on current carrying wires.. |
is the same as moving charges Charges are moving IN the wires |
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Electromagnetic Induction: |
Move a magnet through a coil, get a voltage |
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Faraday's Law: |
Voltage increases with size of loops, number of loops, and how quickly the magnetic field changes. |
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REMEMBER! |
It's not how strong a magnetic field is, but how fast it is changing! (A strong field can help it change faster) |
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Energy Conservation: |
Magnet doesn't want to go into loop |
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Generators |
Motors running backwards More resistance attached, harder to turn |
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Transformers |
Primary and secondary coils Side with more coils has higher voltage BUT lower current MUST have changing current to work |
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Ignition system: |
Really fast changing current 1. Breaker points cause fast change in primary 2. Lots of turns in secondary 3. Big voltage in secondary 4. Spark plug fires |
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When a bar magnet is thrust into a coil of copper wire, the coil tends to |
Repel the magnet as it enters |
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A transformer actually transforms... |
VOLTAGE |
