- Alexander Pope

Charges

positive
negative

Coulomb':s Law
Power source (V = volts)
Resistence (R = ohms, ℮)
Current (I = amps)
Electric Circuits

Series
Parallel

Types of Current

Direct (DC)
Alternating (AC)

Example questions given in class

1. A current of 1 Amp is passing through a lightbulb. There are 100 Volts of potential difference across the filament in the bulb. What is the resistence of the filament?

V = IR; R = V/I, so 100volt / 1 amp = 100 ohms

2. A toaster has a resistence of 15 ohms. If you have a 100 volt battery, what current is needed?

V = IR; I = V/R, so 100 v / 15 ohm = 6.67 amp

3. What is the power of the toaster?

P = IV = 6.67 amp * 100 volts = 667 watt (0.667 kilowatts)

4. Given a 100 watt lightbulb and a 100 volt power source, what is the amperage needed?

P = IV, I = P/V = 100 watt / 100 volt - 1 amp.

Suggested problems from book:
Parallel exercises, group A, page 144 (3rd ed.); page 128 in 2nd edition

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