1. Electrical Circuits

2. Circuits:
A circuit is made up of a power supply, connecting wires & various elements that allow current to leave a power source, travel through the elements & return back to the power source.

3. Common Electric Parts
Battery/Power Source
Bulb

5. Common symbols (cont’d)
Switch
Push-button Switch
Resistor
Voltmeter
Ammeter V A

6. Circuits
Power Supply
- + A v
Ammeter
Resistor
Voltmeter

7. Types of Circuits: There are 2 types of circuits: SERIES PARALLEL
Trick to help identify type of circuit:
Series: Current has only one option to flow
Parallel: Current has more than one option to flow through
There are 2 types of circuits:
1. Series Circuit
2. Parallel Circuit
SERIES
PARALLEL

8. Series Circuits Components are connected end to end
Current only follows one path
If one part of the circuit is broken, the entire circuit will stop functioning
Eg: Christmas tree lights

9. Parallel Circuits Circuit that contains at least one branch
Current can follow at least 2 different paths
If part of the circuit is defective another part may still be able to operate.
Eg: headlights on a car

10. Example Series or Parallel? 2. 1. PARALLEL SERIES A 3. 4. SERIES

11. Adding an Ammeter into a Circuit
In order to measure the current traveling through a circuit, an ammeter must be inserted into the circuit.
An ammeter is always connected inside the circuit in series. A

12. Connecting An Ammeter A) B) C) NO YES YES F) E) D) NO YES NO
In each diagram, is the ammeter hooked up correctly to these circuits? A) B) C) A A NO A
YES
YES F) E) D) NO A
YES NO A A

13. Adding a Voltmeter to a Circuit
In order to measure the voltage traveling through a circuit, a voltmeter must be inserted into the circuit.
A voltmeter is always connected outside the circuit in parallel. V

14. Connecting A Voltmeter
In each diagram, is the voltmeter hooked up correctly to these circuits? V A) B) C) V V NO
YES
YES F) E) D) V
YES V
YES NO V

15. KEY POINTS
Voltmeter – always placed outside of circuit attached in parallel
Ammeter – is always placed inside circuit attached in series

16. Setting up a Circuit PARV acronym P-ower A-mmeter R-esistor
V-olt Meter