1. Circuits

2. In circuits, elements are connected by wires. Any connected region of wire has the same potential. (same color = same potential) The potential difference across an element is the element’s “voltage.”

3. Series Wiring Series wiring means that the devices are connected so that the same electrical current runs through each device.

4. Series Wiring - summary Same current, I Different voltage, V R for each resistor V = V 1 + V 2 We can combine series resistors into one equivalent resistor, R s, R s = R 1 + R 2

5. Equivalent Resistance The resistors in series can be combined into a single equivalent resistor. To the battery, both of these circuits are the same – the battery delivers the same current and the same power

6. Parallel Circuits Parallel wiring means that the devices are connected so that the same voltage is applied across each device.

7. Parallel Circuits - summary

9. Solving Simple Circuits To understand complex circuits… Combine resistors in series and parallel into a fictitious equivalent resistor! Use Ohm’s Law to find the current, I, that the battery supplies (using the equivalent circuit) Work backwards to find the current and voltage for each resistor using Ohm’s law, and properties of series and parallel wiring.

10. Assignment Try the worksheet from yesterday again. New worksheet today – more practice