Unit 8 - Circuits

Circuit Circuit DiagramsDiagrams

Circuits: made up of wires and parts such as ________, light bulbs, _______, or switches.

When diagramming circuits, use ________ to represent parts of the circuit.

Common Electrical Symbols

Straight lines represent

wires.

Battery

Resistor Light Bulb

Switch

NOTE: In many circuit diagrams, any electrical device is shown as a resistor. A resistor is an electrical component that uses energy. Sometimes when showing how a circuit works, light bulbs might be treated like resistors.

Open vs Closed Circuits• Electricity _______ travel through an open

circuit: path is broken.• Electricity can travel easily through a ______

_______: there is a complete path.• A short circuit is usually an accidental extra

path for current to flow.

Series vs Parallel CircuitsParallel Circuits

• Current can take more than one path

• If multiple bulbs are in circuit, if one goes out, the others will __________

• Homes are wired with ________ circuits

Series Circuits Current can only take

one ______ If multiple bulbs in

circuit, if one goes out they all go out

Series circuits would not work in the home because all electrical items would have to be on all the time to keep the circuit closed

Equivalent Resistance – Series Circuit• For a series circuit you

just ___ the resistance of each resistor to find the _____ ________

Equivalent Resistance - Parallel Circuit• To find the resistance in

a parallel circuit you add the _______ of each resistance