Websink Prep UKKS2 ScienceYear 6 chaptersScience textbooksYear 1Year 2Year 3Year 4Year 5Year 6Year 7Year 8Year 9Browse allPast papersFind a tutorBecome a tutor
Primary Science · Year 6Chapter 9 · Cells, brightness and volume
Year 6 · 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)

National Curriculum for England, Key Stage 2 science, Year 6. Content: EL1 associate the brightness of a lamp or the volume of a buzzer with the number and voltage of cells used in the circuit.

Exercise P  Do you remember?

1
FWhat do we call a material that lets electricity flow through it easily? Write the word.
2
FWhat do we call a material that does not let electricity flow through it? Write the word.
3
FWhat is the unit of voltage? Write the word.
4
FWhat is a circuit called if the electricity can flow all the way round it? Write the words.
5
FName the part of a circuit that gives the energy to the circuit. Write the word.
9.1

Cells and their voltage

Year 6
EL1: associate the brightness of a lamp or the volume of a buzzer with the number and voltage of cells used in the circuit
Video lesson: Cells and their voltageComing soon
Story. Ali is building a circuit for school. “I have one cell,” he says. “My friend has two cells, and his bulb looks brighter.” Mrs Chen says, “Each cell gives a voltage. When we join cells end to end, the voltages add up. Let’s find out what that means.”

A cell gives a voltage, measured in volts (V). A standard cell gives 1.5 volts. Cells have a positive end, marked +, and a negative end, marked -.

When cells are joined end to end, with positive to negative, their voltages add up. The total voltage is the number of cells multiplied by 1.5 volts.

1 cell+-1.5 volts2 cells+-+-3.0 volts3 cells+-+-+-4.5 voltseach cell gives 1.5 volts; cells joined end to end add their voltages
One, two and three cells in a row. Their voltages are 1.5 volts, 3.0 volts and 4.5 volts.

The table gives the total voltage for one, two and three cells.

Cells in the circuitTotal voltage (volts)
11.5
23.0
34.5

Key ideas

  • A standard cell gives 1.5 volts.
  • Cells joined end to end, positive to negative, add their voltages.
  • Total voltage = number of cells x 1.5 volts.
  • More voltage means more push on the electricity in the circuit.
Worked example 9.1.1
What is the total voltage of two cells joined end to end? Write the number of volts.

Method. Multiply the number of cells by 1.5 volts.

  1. Count the cells. There are two cells.
    2
  2. Multiply. Each cell gives 1.5 volts, so 2 x 1.5 volts.
    2 x 1.5 = 3.0
  3. Write the answer.
    3.0 volts

Check. The table gives 3.0 volts for two cells. ✓

Worked example 9.1.2
What is the total voltage of three cells joined end to end? Write the number of volts.

Method. Multiply the number of cells by 1.5 volts.

  1. Count the cells. There are three cells.
    3
  2. Multiply. So 3 x 1.5 volts.
    3 x 1.5 = 4.5
  3. Write the answer.
    4.5 volts

Check. Adding 1.5 volts three times gives 4.5 volts. ✓

Worked example 9.1.3
How many more volts does a circuit with three cells have than a circuit with one cell? Write the number of volts.

Method. Subtract the one-cell voltage from the three-cell voltage.

  1. Read the voltages. Three cells give 4.5 volts and one cell gives 1.5 volts.
    4.5 and 1.5
  2. Subtract. The difference is 4.5 minus 1.5.
    4.5 - 1.5 = 3.0
  3. Write the answer.
    3.0 volts

Check. 1.5 + 3.0 = 4.5. ✓

Watch out

Watch out: cells must be joined positive to negative to add their voltages. A cell joined the wrong way round takes away voltage from the others.

Exam tip

Exam tip. Multiply the number of cells by 1.5 volts, and give the unit: volts.

Try it (with your teacher, or a grown-up at home). With a teacher, look at the labels on two cells. Find the + and - ends. Join them end to end, + to -, and read the label or the chart that says the voltage. Never join the two ends of one cell with a wire, because that is a short circuit and makes the cell hot.

Exercise 9A  Cells and their voltage

1
FWhat is the voltage given by one standard cell? Write the number of volts.
2
FWhich end of a cell is marked with a plus sign? Write the word: positive or negative.
3
FWhat is the total voltage of two cells? Write the number of volts.
4
FWhat is the total voltage of three cells? Write the number of volts.
5
FWhen cells are joined end to end, do their voltages add up? Write yes or no.
6
FWhat is the unit of voltage? Write the abbreviation.
7
FWrite the number of volts that one cell adds to a circuit.
8
PSIs the total voltage of four cells 6.0 volts? Write yes or no.
9
PSA circuit has three cells. What is the total voltage? Write the number of volts.
10
PSRuby joins five cells end to end. What is the total voltage? Write the number of volts.
11
PSMo says the total voltage of three cells is 3.0 volts. Is Mo right? Write yes or no.
12
RExplain why cells must be joined positive to negative. Write one sentence.
13
RChallenge: explain why two cells give more voltage than one cell, even though each cell is the same. Write one sentence.
9.2

Brightness of a bulb and the number of cells

Year 6
EL1: associate the brightness of a lamp with the number and voltage of cells used in the circuit
Video lesson: Brightness of a bulb and the number of cellsComing soon
Story. Priya tests a bulb with one cell, then with two cells, then with three. “The bulb gets brighter each time,” she says. Her teacher says, “Let’s repeat each test three times, and record the brightness out of 5 each time, so we can find the mean.”

The brightness of a bulb depends on the voltage across it. More cells joined end to end give a higher total voltage. A higher voltage makes more current flow through the bulb, so the bulb is brighter.

The class rated each bulb brightness out of 5. A rating of 5 is the brightest.

012345brightness rating (out of 5)21 cell42 cells53 cells
Bar chart of bulb brightness: 1 cell rated 2, 2 cells rated 4, 3 cells rated 5, out of 5.

The table gives Priya's three trials for each number of cells, and the mean of the trials.

CellsTrial 1Trial 2Trial 3Mean brightness (out of 5)
12222
24444
35555

Key ideas

  • More cells give a higher total voltage.
  • A higher voltage makes a bulb brighter.
  • Brightness is recorded as a rating out of 5, and repeats give a mean.
  • Keep the bulb, the wires and the holder the same in a fair test.
Worked example 9.2.1
Look at the table in section 9.2. What is the mean brightness with two cells? Write the number out of 5.

Method. Read the mean column.

  1. Read the row. The row for two cells gives three trials of 4, 4 and 4.
    4, 4, 4
  2. Write the mean. The mean brightness is 4 out of 5.
    4
  3. Write the answer.
    4 out of 5

Check. 4 + 4 + 4 = 12, and 12 divided by 3 is 4. ✓

Worked example 9.2.2
How much brighter was the bulb with three cells than with one cell? Write the rating difference, out of 5.

Method. Subtract the one-cell rating from the three-cell rating.

  1. Read the ratings. The three-cell bulb is rated 5, and the one-cell bulb is rated 2.
    5 and 2
  2. Subtract. The difference is 5 minus 2.
    5 - 2 = 3
  3. Write the answer.
    3

Check. 2 + 3 = 5. ✓

Worked example 9.2.3
Which number of cells gives the brightest bulb? Write the number of cells.

Method. Find the highest rating.

  1. Read the ratings. The ratings are 2, 4 and 5 for one, two and three cells.
    5
  2. Write the answer. The highest rating is 5, for three cells.
    3
  3. Write the answer.
    3 cells

Check. The bulb with three cells is the brightest. ✓

Watch out

Watch out: brightness is a rating out of 5 in this table. Do not compare it with a voltage; say the bulb is brighter because its total voltage is higher.

Exam tip

Exam tip. When you link brightness to the cells, say that more cells give a higher voltage, and that makes the bulb brighter.

Try it (with your teacher, or a grown-up at home). With a teacher, build a circuit with one cell and one bulb in a holder. Compare the brightness with a second cell added, joined end to end. Use the same bulb each time. Give each bulb a rating out of 5, and repeat the test three times. Switch off the circuit between tests.

Exercise 9B  Brightness of a bulb and the number of cells

1
FLook at the bar chart in section 9.2. What is the brightness rating for two cells? Write the number out of 5.
2
FWhat is the brightness rating for one cell? Write the number out of 5.
3
FWhich number of cells gives the brightest bulb in the table? Write the number of cells.
4
FWhat is the mean brightness with three cells, from the three trials of 5, 5 and 5? Write the number out of 5.
5
FWhat is the mean brightness with one cell, from the trials of 2, 2 and 2? Write the number out of 5.
6
FHow many more out of 5 is the brightness with two cells than with one cell? Write the number.
7
FWhat is the total voltage of the cells for the brightest bulb? Write the number of volts.
8
PSAli says a bulb with two cells is brighter than a bulb with three cells. Is Ali right? Write yes or no.
9
PSPriya's bulb with one cell is rated 2. She adds a second cell, and the bulb is rated 4. By how many points did the rating rise? Write the number.
10
PSPlan a fair test to compare the brightness with one cell and two cells. Write one variable that must stay the same.
11
RExplain why the bulb is brighter with three cells than with one cell. Write one sentence.
12
RChallenge: explain why three repeats of each trial, with the mean, give a more reliable brightness than one trial. Write one sentence.
9.3

Volume of a buzzer and the number of cells

Year 6
EL1: associate the volume of a buzzer with the number and voltage of cells used in the circuit
Video lesson: Volume of a buzzer and the number of cellsComing soon
Story. Tom tests a buzzer with one cell, then with two, then with three. The class rates how loud each buzzer is, out of 5. “The buzzer is louder with more cells,” says Tom. “Let’s write the ratings down, and see if the pattern holds.”

A buzzer makes a sound when a current flows through it. A higher voltage makes more current flow, so the buzzer can be louder. The loudness in this table is a rating given by the class, out of 5.

As with the bulb, more cells give a higher total voltage. Each extra cell adds 1.5 volts.

012345loudness rating (out of 5)21 cell32 cells53 cells
Bar chart of buzzer loudness: 1 cell rated 2, 2 cells rated 3, 3 cells rated 5, out of 5.

The table gives the total voltage and the ratings for each number of cells.

Number of cellsTotal voltage (V)Bulb brightness (out of 5)Buzzer loudness (out of 5)
11.522
23.043
34.555

Key ideas

  • More cells give a higher voltage, and a louder buzzer.
  • Loudness is recorded as a rating out of 5, using the same scale each time.
  • A buzzer needs a complete circuit to make a sound.
  • Compare the ratings with the table, not with memory.
Worked example 9.3.1
Look at the table in section 9.3. What is the buzzer rating with two cells? Write the number out of 5.

Method. Read the row for two cells.

  1. Read the row. The row for two cells gives a loudness of 3 out of 5.
    3
  2. Write the answer. So the rating is 3 out of 5.
    3 out of 5
  3. Write the answer.
    3 out of 5

Check. The rating goes up as the cells increase. ✓

Worked example 9.3.2
How much louder, in rating points, is the buzzer with three cells than with one cell? Write the number of points.

Method. Subtract the one-cell rating from the three-cell rating.

  1. Read the ratings. The ratings are 5 for three cells and 2 for one cell.
    5 and 2
  2. Subtract. The difference is 5 minus 2.
    5 - 2 = 3
  3. Write the answer.
    3 points

Check. 2 + 3 = 5. ✓

Worked example 9.3.3
What is the total voltage with three cells, according to the table? Write the number of volts.

Method. Read the voltage column.

  1. Read the table. Three cells give 4.5 volts.
    4.5
  2. Write the answer. So the total voltage is 4.5 volts.
    4.5 volts
  3. Write the answer.
    4.5 volts

Check. 3 x 1.5 = 4.5. ✓

Watch out

Watch out: the buzzer rating is a class rating out of 5. It is not a measurement in decibels, so do not give it a unit.

Exam tip

Exam tip. Link the volume to the cells: more cells, a higher voltage, and a louder buzzer.

Try it (with your teacher, or a grown-up at home). With a teacher, connect a buzzer to one cell, then to two cells joined end to end. Ask the class to rate each buzzer out of 5, using the same scale each time. Write the ratings in a table. Do not hold the buzzer near your ears.

Exercise 9C  Volume of a buzzer and the number of cells

1
FWhat is the buzzer loudness rating for one cell? Write the number out of 5.
2
FWhat is the buzzer loudness rating for three cells? Write the number out of 5.
3
FWhat is the total voltage of two cells in the table in section 9.3? Write the number of volts.
4
FWhich number of cells gives the loudest buzzer? Write the number of cells.
5
FBy how many points does the buzzer rating rise from two cells to three cells? Write the number of points.
6
FWhat is the total voltage with one cell, according to the table? Write the number of volts.
7
FIs the buzzer louder with two cells than with one cell? Write yes or no.
8
PSWhich two numbers of cells give a buzzer rating that differs by 1 point? Write the two numbers of cells.
9
PSRuby says the buzzer is louder with 3 cells, so its total voltage must be 3 volts. Is Ruby right? Write yes or no.
10
PSA buzzer is rated 3 with two cells. Ali adds one more cell, and the rating is 5. What is the total voltage now? Write the number of volts.
11
RExplain why adding a cell makes the buzzer louder. Write one sentence.
12
RChallenge: explain why a buzzer rating is a class rating, and why the class should use the same scale each time. Write one sentence.
9.4

A complete circuit

Year 6
EL1: the circuit must be complete for a lamp or buzzer to work, and the number of cells changes the brightness or volume
Video lesson: A complete circuitComing soon
Story. Sam joins a cell to a bulb with one wire. The bulb does not light. “Why not?” he asks. Mrs Chen says, “The electricity must be able to flow all the way round. Add a second wire to make a loop, and try again.”

A complete circuit is a loop. Electricity flows from the positive end of the cell, round the wires and through the bulb or the buzzer, and back to the negative end.

If the loop is broken, anywhere, the electricity cannot flow and the bulb or buzzer does not work. Each part of a circuit needs to be connected.

+-bulb1 cell in a loop with a bulb
A loop with one cell and a bulb, joined by wires all the way round.
+-+-bulb2 cells in a loop with a bulb
A loop with two cells in a row and a bulb, joined all the way round.

The table names the parts of a simple circuit, and what each one does.

PartWhat it does
cellprovides the energy; it has a positive and a negative end
wirecarries the current round the loop
bulblights up when current flows through it
buzzermakes a sound when current flows through it

Key ideas

  • A complete circuit is a loop with no gaps.
  • Electricity flows from the positive end of the cell, round the loop, and back to the negative end.
  • A bulb or buzzer works only when it is part of a complete loop.
  • More cells give more voltage, which makes a bulb brighter or a buzzer louder.
Worked example 9.4.1
Look at the picture in section 9.4 with one cell. Is the loop complete? Write yes or no.

Method. Check the wires round the loop.

  1. Check the loop. The wires go all the way round, and the bulb is in the loop.
    all the way
  2. Decide. So the loop is complete, and the answer is yes.
    yes
  3. Write the answer.
    yes

Check. Every part is connected in the loop. ✓

Worked example 9.4.2
A wire is removed from the loop. Does the bulb light? Write yes or no.

Method. Think about the broken loop.

  1. Think about the gap. With a wire removed, the loop has a gap, so the electricity cannot flow.
    gap
  2. Decide. So the bulb does not light, and the answer is no.
    no
  3. Write the answer.
    no

Check. A gap in the loop stops the current. ✓

Worked example 9.4.3
What do we call a circuit with all the wires joined in a loop? Write the words.

Method. Recall the name.

  1. Recall. A circuit joined all the way round is a complete circuit.
    complete circuit
  2. Check the meaning. Complete means there are no gaps in the loop.
    no gaps
  3. Write the answer.
    complete circuit

Check. Complete means there are no gaps. ✓

Watch out

Watch out: a bulb may not light because the loop is broken, not because the bulb is faulty. Check every connection first.

Exam tip

Exam tip. When a circuit does not work, say that the loop must be complete, and check each connection.

Try it (with your teacher, or a grown-up at home). With a teacher, build a loop with one cell, one bulb in a holder and two wires. Make the bulb light. Then remove one wire, and watch the bulb go out. Put the wire back. Never connect a wire directly across the two ends of one cell.

Exercise 9D  A complete circuit

1
FDoes a bulb need a complete loop to light? Write yes or no.
2
FWhich part of the circuit gives the energy? Write the word.
3
FWhich part of the circuit lights up when current flows through it? Write the word.
4
FWhich part of the circuit carries the current round the loop? Write the word.
5
FIs there a gap in a loop with a wire removed? Write yes or no.
6
FDoes the bulb light when there is a gap in the loop? Write yes or no.
7
FWhat is the name of a circuit with all the wires joined in a loop? Write the two words.
8
PSWhich way does electricity flow round the loop, from the positive or the negative end of the cell? Write the word.
9
PSPriya says a bulb works in a circuit with a gap if the cell is strong enough. Is Priya right? Write yes or no.
10
PSAli has two cells in a complete loop with a bulb. What is the total voltage? Write the number of volts.
11
RExplain why a bulb in a complete loop lights, but the same bulb in a loop with a gap does not. Write one sentence.
12
RExplain why a short wire that joins the two ends of one cell is dangerous. Write one sentence.
13
RChallenge: explain why a circuit with two cells in a complete loop works better than one with a gap and two cells. Write one sentence.
9.5

A fair test with cells, and safety

Year 6
EL1: plan and read a fair test on the number of cells; WS1 and WS2: control variables and take repeat readings
Video lesson: A fair test with cells, and safetyComing soon
Story. Aisha plans a test to find out how the number of cells changes a bulb. “I must keep the bulb the same, and change only the number of cells,” she says. Her teacher adds, “And always keep the cells away from metal objects, and never connect the two ends of one cell with a wire.”

A fair test changes only one variable. In this test, the changed variable is the number of cells. The measured variable is the brightness or the loudness, rated out of 5. The fixed variables are kept the same: the same bulb, the same wires, the same bulb holder and the same type of cell.

Safety is part of planning: use low-voltage cells only, and always work with a teacher present.

Key ideas

  • A fair test changes only the number of cells.
  • The fixed variables are the same bulb, wires, holder and type of cell.
  • Repeat each trial, and find the mean.
  • Never connect a wire straight across the two ends of one cell.
Worked example 9.5.1
In Aisha's test, which variable is the changed variable? Write the words.

Method. Find the thing that changes on purpose.

  1. Read the plan. Aisha changes the number of cells on purpose.
    number of cells
  2. Write the words. So the changed variable is the number of cells.
    number of cells
  3. Write the answer.
    the number of cells

Check. The bulb stays the same. ✓

Worked example 9.5.2
Aisha uses a different bulb with two cells. Is her test fair? Write yes or no.

Method. Count the changes.

  1. Count the changes. She changes the number of cells and also the bulb.
    two changes
  2. Decide. Changing two things is not fair, so the answer is no.
    no
  3. Write the answer.
    no

Check. Only one variable should change. ✓

Worked example 9.5.3
How many fixed variables are listed in section 9.5? Write the number.

Method. Count the fixed variables in the list.

  1. Count. The fixed variables are the bulb, the wires, the bulb holder and the type of cell.
    four
  2. Write the number. So there are four fixed variables.
    4
  3. Write the answer.
    4

Check. Keeping four things the same makes the test fair. ✓

Watch out

Watch out: a short circuit can make a cell and its wires hot. Connect the wires to the cell ends only through the bulb and holder.

Exam tip

Exam tip. When you plan a test on cells, name the changed variable, the measured variable and two fixed variables.

Try it (with your teacher, or a grown-up at home). Plan a fair test, with a teacher, on the number of cells and the brightness of a bulb. Write the changed variable, the measured variable, and three fixed variables, then carry out the test with three repeats for each number of cells.

Exercise 9E  A fair test with cells, and safety

1
FIn a test on cells and brightness, what is the changed variable? Write the words.
2
FIn the same test, what is the measured variable? Write the word.
3
FWhich fixed variable is the type of bulb used in the test? Write the words.
4
FIs it safe to join a wire straight across the two ends of one cell? Write yes or no.
5
FShould a pupil use mains electricity in this test? Write yes or no.
6
FHow many fixed variables are listed in section 9.5? Write the number.
7
PSRuby changes the number of cells and the bulb holder in one test. Is this a fair test? Write yes or no.
8
PSTom wants to repeat the test three times for each number of cells. What does this help him to find? Write one word.
9
PSPriya connects the two ends of one cell with a wire, to see if it gets warm. Is this safe? Write yes or no.
10
PSWrite one fixed variable for a test on the number of cells and the buzzer loudness. Write one thing.
11
RExplain why a fair test on the number of cells must keep the bulb the same. Write one sentence.
12
RChallenge: explain why a teacher must be present when cells and bulbs are used in this test. Write one sentence.

Chapter summary

SkillMethod
Voltage of cellsA standard cell gives 1.5 volts. Cells joined end to end add their voltages.
BrightnessMore cells give a higher voltage, which makes a bulb brighter.
VolumeMore cells give a higher voltage, which makes a buzzer louder.
Complete circuitA bulb or buzzer works only in a complete loop with no gaps.
Fair test and safetyChange only the number of cells. Keep the bulb, wires and holder the same. Never join a wire across a cell.

Can you…?

  • I can say that a cell gives 1.5 volts, and cells joined end to end add their voltages
  • I can work out the total voltage of a number of cells
  • I can say how more cells make a bulb brighter, using a table of ratings
  • I can say how more cells make a buzzer louder, using a table of ratings
  • I can explain why a circuit must be a complete loop
  • I can plan a fair test on the number of cells, and say how to keep it safe

Key terms

cell
a part of a circuit that gives a voltage, with a positive and a negative end
voltage
the push that makes electricity flow in a circuit, measured in volts
volt (V)
the unit of voltage
complete circuit
a circuit joined all the way round with no gaps, so current can flow
bulb
a component that lights up when current flows through it
buzzer
a component that makes a sound when current flows through it
short circuit
a wire joined straight across the two ends of a cell, which makes it hot and is dangerous
brightness rating
a rating out of 5 given to the brightness of a bulb, in this chapter
loudness rating
a rating out of 5 given to how loud a buzzer is, in this chapter

Exercise 9Z  Check-up

1
What is the voltage of one standard cell? Write the number of volts.
2
What is the total voltage of three cells joined end to end? Write the number of volts.
3
Look at the table in section 9.2. What is the mean brightness with three cells? Write the number out of 5.
4
Look at the table in section 9.3. What is the buzzer loudness with one cell? Write the number out of 5.
5
Two cells give 3.0 volts. How many more volts do three cells give than two cells? Write the number of volts.
6
Name the part of a circuit that lights up when current flows through it. Write the word.
7
Name the part of a circuit that carries the current round the loop. Write the word.
8
Does a bulb light when the loop has a gap? Write yes or no.
9
What is the name of a circuit that is joined all the way round with no gaps? Write the two words.
10
Explain why a bulb with three cells is brighter than a bulb with one cell. Write one sentence.

Total 17 marks. Allow about 17 minutes.

Exercise 9X  Practice test questions

1
PSA standard cell gives 1.5 volts. Write the total voltage of four cells joined end to end, in volts.[2 marks]
2
FA class tested a bulb with 1, 2 and 3 cells. The brightness ratings out of 5 were 2, 4 and 5. Write the rating for the bulb with two cells.[1 mark]
3
PSA class rated a buzzer with 1, 2 and 3 cells. The loudness ratings out of 5 were 2, 3 and 5. Write the difference in rating between one cell and three cells.[2 marks]
4
RExplain why a bulb with two cells is brighter than a bulb with one cell. Write one sentence.[2 marks]
5
FWrite the total voltage of three cells joined end to end, in volts.[1 mark]
6
RA circuit has a gap in its loop. Does the bulb light? Write yes or no, and give the reason in one word.[2 marks]
7
FA fair test on cells keeps the same bulb, the same wires and the same holder. Write the changed variable in this test.[1 mark]
8
RExplain why a teacher should check the connections before cells are used. Write one sentence.[2 marks]
9
PSA class rated a buzzer with two cells as 3 out of 5. Ruby says the rating of 3 means the buzzer has 3 volts. Is Ruby right? Write yes or no.[2 marks]
10
RWrite one reason why the same bulb must be used in each trial of a test on cells. Write one sentence.[2 marks]
← Chapter 8: How we seeChapter 10: Components, switches and circuit symbols →

Websink Prep UK is an independent site. It is not affiliated with, endorsed by or sponsored by AQA, Pearson Edexcel, OCR, WJEC, Eduqas, CCEA, SQA, GL Assessment, CEM or the Department for Education. All exam board names and trademarks belong to their owners. Past papers are linked from the exam boards' own websites and are not hosted here.

About Websink Prep UK · Find a tutor · Privacy · Terms · Cookie settings