1. Parallel circuits
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Learning Objective: Predict and explain measurements of current in different parts of parallel circuits
Starter: Quick Quiz/Run around.

2. Which of these statements is true?
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Which of these statements is true?
A Plastic is a conductor because it lets electricity flow through it.
B Plastic is an insulator because it lets electricity flow through it.
C Metals are conductors because they let electricity flow through them.
D Metals are insulators because they let electricity flow through them.

3. 2 What do these symbols show? A a cell and a bulb
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2 What do these symbols show?
A a cell and a bulb
B a cell and a switch
C a bulb and a switch
D a switch and a motor

4. 3 Which instrument would you use to measure current?
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3 Which instrument would you use to measure current?
A an ammeter B a cell
C a motor D voltmeter

5. How big would the current be at X, Y and Z?
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How big would the current be at X, Y and Z?
A It would be biggest at X and smallest at Z.
B It would be biggest at Z and smallest at X.
C There would be no current at Y.
D It would be the same at all three places.

6. You can make the current in a circuit smaller by:
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You can make the current in a circuit smaller by:
A putting a switch in the circuit.
B putting more bulbs in the circuit.
C taking some bulbs out of the circuit.
D putting more cells in the circuit.

7. B a kind of liquid inside the wires.
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6 Electricity is:
A a source of energy.
B a kind of liquid inside the wires.
C tiny particles called electrons flowing through the wires.
D tiny particles called atoms flowing through the wires.

8. Think about a heating system
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Think about a heating system

9. Series - the current goes in one loop only
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Series - the current goes in one loop only
Parallel - the current splits into more than one loop

10. Parallel circuits
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A parallel circuit is one where the current has a “choice of routes”:

11. Parallel Circuits and Switches
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First, connect your bulbs and switch all in series as shown below. + - A B
Next, connect one bulb and switch in parallel to the other bulb like this: + - A B

12. Advantages of parallel circuits…
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There are two main reasons why parallel circuits are used more commonly than series circuits:
Extra appliances (like bulbs) can be added without affecting the output of the others
If one appliance breaks it won’t affect the others either