1. Write this in your notebook.
5.3 Dynamic Electricity
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There are 2 types of electricity
Static electricity: when electrical charges are at rest (as we have already covered).
Dynamic electricity: when electrical charges are in motion (in a wire) causing an electric current to flow.

2. Write this in your notebook.
Electric Current
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Electric current is the orderly flow of electrons through a conductor. (Fig. 5.19)
Electron flow: the direction the electrons actually move (- to +)
Conventional current: the direction positive particles would flow if they could move (+ to -). BUT THEY DON’T MOVE! Only the electrons move.

3. Conductors & Insulators

4. Insulators:
Substance that does NOT allow electric current to pass. Most non-metals.
Ex.
Plastic, Wood, Paper, Rubber, Glass, Ceramics

5. Conductors:
Substance that allows electric current to pass. Most metals.
Ex.
Metal wires (ex. Aluminum or copper)
Graphite rods

6. Pure water is NOT a good conductor
Nichrome is a POOR conductor
used in resistors, toasters, radiators…

7. Conductance of a wire depends on:
Length
Diameter
Temp
Material
Copper is excellent
Nichrome is NOT
SHORT
Good
conductance
FAT
COLD

8. Ex #1 Ex #2 Which is a better conductor? Plastic Copper Wood Iron
SHORT
FAT
COLD
Wood
Iron
Ex #2
Which metal wire has the best conductance?

9. Ex #3 Which wire is the best conductor? SHORT FAT COLD Wood 55oC
Copper
25oC
SHORT
FAT
COLD
Copper
25oC
Copper
55oC
Aluminum
25oC
Copper
5oC

10. Write this in your notebook.
Important Points:
Copper is an excellent conductor
Wires that are:
SHORT
FAT
COLD
Nichrome is an excellent insulator & a terrible conductor!
Write this in your notebook.
have a high conductance