1. Series Circuits Circuits in which there is only one path for current to flow through All elements of the circuit (resistors, switches etc…) are in the same path – “In Series” with each other. The resistance in the circuit is the sum of the resistances in the series. Current in the circuit is the same in all parts of the circuit. I = V/R Different components use (or “drop”) different voltages based on their resistance. V = IR If one element fails (creating an open circuit), no current will flow

2. Electrical Circuit Symbols

3. Series Circuit

4. Parallel Circuits Circuits in which there is more than one path for current to flow through. Elements of the circuit (resistors, switches etc…) can be in the different “Parallel” paths The different Parallel paths can have multiple elements that are in Series with each other. The voltage across each parallel path is the same. Current in the different parallel paths can be different (with different resistances) or the same. (with equal resistances) I = V/R If one element fails (creating an open circuit), no current will flow through that path, but the other paths will be unaffected, maintaining their individual currents.

5. Parallel Circuit

6. Combination Circuit http://www.glenbrook.k12.il.us/gbssci/phys/Class/circuits/u9l4e.html http://www.glenbrook.k12.il.us/gbssci/phys/Class/circuits/u9l4e.html In combination circuits, both series and parallel parts exist. The resistance of a parallel section can be represented by a single net resistance in series with the rest of the circuit.