1. PSC 151 Laboratory Activity 9 Electric Circuits II Series and Parallel Connections

2. Series Connection: When devices are connected in series there is only one path for the current to follow and therefore, the same current must flow through each device. Series connections are made by connecting opposite parts of two devices, e.g. terminal 1 of lamp A to terminal 2 of lamp B OR terminal 2 of lamp A to terminal 1 of lamp B. The negative terminal of Battery #1 to the positive terminal of Battery #2 OR positive terminal of Battery #1 to the negative terminal of Battery #2

3. Parallel Connection: When devices are connected in parallel there are multiple paths for the current to follow. Different currents will flow through each device depending by each device's electrical properties. Parallel connections are made by connecting the same parts of two devices, e.g. terminal 1 of lamp A to terminal 1 of lamp B AND terminal 2 of lamp A to terminal 2 of lamp B. The positive terminal of Battery #1 to the positive terminal of Battery #2 AND the negative terminal of Battery #1 to the negative terminal of Battery #2.

4. Characteristics of Series Circuits: 1. One path for current to follow 2. Unlike parts connected 3. One connecting wire for each pair of devices 4. Never more than one wire connected at any point Characteristics of Parallel Circuits: 1. Multiple paths for current to follow 2. Like parts connected 3. Two connecting wires for each pair of devices 4. May have more than one wire connected at any point

5. Connecting One Lamp to One Battery Connect the positive (or negative) terminal of Battery #1 to terminal #1 (or #2) of lamp A. Connect the other terminal Battery #1 to the other terminal of lamp A. Current Flow

6. Connecting Two Lamps in Series to One Battery Connect OPPOSITE terminals of lamps A & B A1 to B2 (or A2 to B1) Connect Battery #1 to the open terminals of lamps A & B A1 and B2 (or A2 and B1) Current Flow

7. Connecting Two Batteries in Series to One Lamp Connect OPPOSITE terminals of Batteries 1 & 2 1- to 2+ Connect open terminals of batteries 1 & 2 to lamp A

8. Connecting Two Lamps in Parallel to One Battery Connect Like terminals of lamps A & B A1 to B1 and A2 to B2 A1 and B1 become the same terminal as do A2 and B2 Connect one terminal of Battery #1 to terminal 1 of either lamp A or B Connect the other terminal of Battery #1 to terminal 2 of either lamp A or B Current Flow

9. Connecting Two Batteries in Parallel to One Lamp Connect Like terminals of Batteries 1 & 2 1+ to 2+ and 1- to 2- Connect either +terminal and either - terminal of batteries 1 & 2 to lamp A