9.1 Parallel Circuits

• Physics
• Secondary Education
• Age 12,13

20 April 2023

Unit 9.1 Parallel Circuits

Content objectives

• Explain current divides in a parallel circuit
• Calculate missing current values in parallel circuits
• Measure the current in parallel circuits
•  Describe the advantages of parallel circuits over series circuits

• What appliances at home use electricity to work?

Purpose of this lesson

• What do you know about an "electric circuit "?

What I Know:

Activity 1

20 April 2023

Unit 9.1 Parallel Circuits

Study the diagrams below:

circuit diagram A

circuit diagram B

Which diagram shows a SERIES circuit?

1. circuit diagram A
2. circuit diagram B

Study the diagrams below:

circuit diagram A

circuit diagram B

Series Circuit

• There is only ONE path for the current to flow.

• Will the bulb light up if the switch is open?

Will the bulb light up if the switch is open?

YES

NO

Parallel Circuit

• There is more than one path for the current to flow.

• Will both bulbs still light up if the wire is broken, as shown in the diagram?

Will both bulbs still light up if the wire is broken, as shown in the diagram?

YES

NO

Ammeters

• What do ammeters measure in a circuit?

Total Electric Current 

• What is the value of A1 if A4 is 5 amperes?
• What is the value of A3 if A2 is 3 amperes?

State the rule about the total electric current in a parallel circuit. "The current through the cell is equal to the ________ of the current in a parallel circuit."

Calculating current

• What is the value of x in the circuit diagram to the right?

Activity 2

Plenary (Sharing)

• Describe the diagram.
• Share how you calculated the current.

Activity 3

What's next?

End of Unit 6 Test on Tuesday, 25th of April 2023