Chapter 9: Cells, brightness and volume

By the end of this chapter you will be able to

• Say that a cell gives a voltage, and that cells joined end to end add their voltages
• Find the total voltage of cells in a circuit, using 1.5 volts for each cell
• Describe how more cells, and a higher voltage, make a bulb brighter
• Describe how more cells, and a higher voltage, make a buzzer louder
• Explain that a circuit must be a complete loop for a bulb or a buzzer to work
• Plan and read a fair test on the number of cells, keeping the other variables the same

You should already know

• Electricity and circuits from Year 4 Science, including cells, bulbs and buzzers at a simple level
• Fair tests, tables and bar charts (Chapter 1 of this book)

Where this leads

• Components and circuit symbols, including switches (Year 6 Science, Chapter 10)