1. Circuits – how we get electricity to do work!
(beginning to 5:19)
(similar)
(Eureka)
(how do lithium ion batteries work?)
11.2 Electric Circuits (page 447 – 454)

2. Learning Goals:
I can draw series and parallel circuit diagrams and explain the function of each circuit component
I can identify electrical quantities and their units, and measure these quantities in an operating circuit
I can explain and investigate the concepts of electric current, potential difference, and resistance in a simple circuits
I can analyze how adding loads or changing resistance will affect series and parallel circuits

3. What is this?
How would you describe/define this?

4. Electric Circuit: A closed path along which electrons that are powered by an energy source can flow.

5. What is needed to make a circuit work?

6. Parts of a Circuit
1. Electrical Load: Anything that converts electrical energy into another form of energy, such as sound, heat, or light.

7. Electrical Loads – Schematic Diagram Symbols
light bulb resistor motor

8. Parts of a Circuit
2. Connectors: Provide a path for electric current to flow to each part of the circuit.

9. Wire Connectors – Schematic Diagram Symbols

10. Parts of a Circuit
3. Electric Source: Where the electricity comes from.

11. Electric Source – Schematic Diagram Symbols
Negative terminal
Positive terminal - +
Battery or 2cells
AC Source (i.e. plug)
Cell

12. Parts of a Circuit
4. Switches: A control device
completes or breaks the circuit to which it is attached
NOT necessary for a circuit to work!

13. Switches – Schematic Circuit Diagram Symbols
open (off) closed (on)

14. Open Circuits
An OPEN CIRCUIT is a circuit that contains a gap or a break.
If there is a break, electrons CAN’T flow and the load won’t work

15. Closed Circuits
A CLOSED CIRCUIT is a circuit that does not contain a gap or break.
- If there is no break, then electrons CAN flow and the load will work

16. Closed Electric Circuit

17. Open Electric Circuit

18. Types of Circuits
A SERIES CIRCUIT is a circuit in which there is ONLY ONE pathway along which electrons can flow. S L1 L2 L3
Examples: S L1

19. Types of Circuits
A PARALELL CIRCUIT is a circuit in which there is MORE THAN ONE pathway along which electrons can flow.
Examples:

20. Types of Circuits
A COMBINATION CIRCUIT is a circuit in which parts are in series, and parts are in parallel.
Examples:

21. Think. Pair. Share. Which resistors are in series with each other?
Which resistors are in parallel with each other? L2 L3 L4 L1 L5 L6 L7 L8
L10 L9 S1 S2
L12
L11

22. Drawing Electric Circuits

23. Drawing Circuits
A CIRCUIT DIAGRAM is a simplified drawing of an electrical circuit.
Symbols are used to represent each part of a circuit
Always use a ruler
It’s a universal system

24. Try This.
Draw the schematic circuit diagram of this circuit picture:

25. Try This.
Answer:
Rotation of the whole circuit or the amount of connector do not matter – but try to use only as much connector as required to make the diagram look neat. or

26. Try This.
Draw the schematic circuit diagram of this circuit picture:

27. Try This.
Answer:
Connector lines must be straight.

28. Try This.
Draw the schematic circuit diagram of this circuit picture:

29. Try This.
This is incorrect.

30. Try This.
Answer:
Getting the order of components correct is important.

31. Try This.
Draw a circuit with a source that leads out the negative end into a light bulb, followed by an open switch, a motor, another light bulb, a resistor, and then back into the source.

32. Try This.
Draw a circuit with a source that leads out the negative end into a light bulb, followed by an open switch, a motor, another light bulb, a resistor, and then back into the source.

33. Turn the light ON!
Using the equipment provided (tin foil, battery, light), make the light go on! Come up with at least 3 different ways to arrange the equipment and turn on the light. Draw a picture of each of your arrangements. Note: if something gets hot….disconnect!

34. Discussion What did we need to make the light go on?
What is this called?
What is a short circuit?