AQA GCSE Combined Science: Trilogy Physics Paper 1 (Foundation), 2024: Question 6

12 marks · Standard Demand difficulty · Short Answer

Identify energy stores, recall and apply power equations, and state mains electricity properties related to an electric whisk.

Practise this question

Question

The image shows a multi-part physics exam question about an electric whisk. It includes a photograph of a white handheld electric whisk with a metal beater attached. The questions ask students to identify energy stores, write and use the equation for power and work done, select the correct equation for power in terms of current and resistance, perform a power calculation requiring unit conversion from milliamperes, and state the standard UK mains potential difference.
Question text

06 Figure 10 shows an electric whisk that plugs into the mains electricity supply.

The whisk can mix food by spinning a beater.

Figure 10

06.1 Give two energy stores that increase when the whisk is switched on.

[2 marks]

Use the Physics Equations Sheet to answer questions 06.2 and 06.3.

06.2 Work is done by the whisk when it is used to mix food.

Write down the equation that links power (P), time (t) and work done (W).

[1 mark]

06.3 The power output of the whisk is 92 W.

Calculate the time for the whisk to do 23 000 J of work.

[3 marks]

Time = s

Use the Physics Equations Sheet to answer questions 06.4 and 06.5.

06.4 Which equation links current (I), power (P) and resistance (R)?

[1 mark]

Tick ( ) one box.

I

P = 2

R

P = I R2

I2

P =

R

P = I2 R

06.5 The current in the whisk is 500 mA.

The resistance of the whisk is 640 Ω.

Calculate the power of the whisk.

[3 marks]

Power = W

The whisk has several settings that allow the beater to spin at different speeds.

A faster beater speed needs a greater power input from the mains electricity supply.

06.6 What is the potential difference between the live wire and neutral wire in the

mains electricity supply?

[1 mark]

*26* V

06.7 Changing the beater speed does not change the potential difference between the live

wire and neutral wire.

The power input to the whisk changes because the current in the whisk changes.

Complete the sentence.

[1 mark]

When the beater speed increases, the current in the whisk increases because the

resistance of the whisk .

Mark scheme

Show the mark scheme The mark scheme for question 6 provides the following answers: 06.1 accepts kinetic energy and internal/thermal energy; 06.2 is power = work done / time; 06.3 shows the calculation 23,000 divided by 92 equals 250 seconds; 06.4 identifies P = I squared R as correct; 06.5 shows converting 500 mA to 0.5 A and calculating 0.5 squared times 640 to get 160 Watts; 06.6 is 230 Volts; and 06.7 is 'decreases'.

Question 6

AO /

Question Answers Extra information Mark

Spec. Ref.

06.1 ignore sound AO1

6.2.4.2

kinetic energy (of the beater / 1 6.1.2.1

food) 6.1.1.1

internal / thermal energy (of the 1

surroundings / whisk / food)

AO /

Spec. Ref.

06.2 work done 1 AO1

power =

time 6.1.1.4

or

W

P =

t

AO /

Spec. Ref.

06.3 23 000 1 AO2

92 =

time 6.1.1.4

23 000

time = 1

250 (s) 1

AO /

Spec. Ref.

06.4 P = I2 R 1 AO1

– – – 6.2.4.1

AO /

Spec. Ref.

06.5 I = 0.500 A 1 AO2

6.2.4.1

2 17

P = 0.500 × 640 allow a correct substitution of an 1

incorrectly / not converted

current

P = 160 (W) allow a correct calculation using 1

an incorrectly / not converted

current

AO /

Spec. Ref.

06.6 230 (V) 1 AO1

6.2.3.2

AO /

Spec. Ref.

06.7 decreases 1 AO1

6.2.4.1

Total Question 6 12

How to answer it

Energy, Power, and Mains Electricity

What this question tests

This question assesses your ability to identify energy stores, recall and use power equations, perform unit conversions (milliamps to Amps), and recall standard facts about the UK mains electricity supply.

Part 06.1

Energy Stores

Correct Answers

  • Kinetic energy (of the beater or food)
  • Internal / Thermal energy (of the surroundings, whisk, or food)

Exam Technique

The question asks for stores. While sound is produced, the exam board explicitly says to ignore sound because sound is a way of transferring energy, not a way of storing it.

Parts 06.2 & 06.3

Power and Work Done

Key Equation

Power = Work Done ÷ Time

P = W / t

Calculation: Finding Time

The whisk has a power of 92 W and does 23,000 J of work.

  1. Substitute values: 92 = 23,000 / t
  2. Rearrange: t = 23,000 / 92
  3. Calculate: 250

Final Answer: 250 s

[1 mark] for the correct equation. [3 marks] for the calculation: substitution, rearrangement, and correct answer.
Parts 06.4 & 06.5

Electrical Power

Correct Equation

Power = Current² × Resistance

P = I²R

Calculation: Power with Unit Conversion

Current (I) = 500 mA | Resistance (R) = 640 Ω

  1. Convert units: 500 mA ÷ 1000 = 0.5 A
  2. Substitute: P = 0.5² × 640
  3. Calculate: P = 0.25 × 640 = 160

Final Answer: 160 W

Common Error: The "milli" Trap

Many students forget to convert mA to A. If you use 500 in the equation, you will lose marks. Always check if a prefix like 'milli' or 'kilo' is used!

Parts 06.6 & 06.7

Mains Supply and Resistance

Mains Voltage

In the UK, the potential difference between the live and neutral wire is a standard 230 V. This is a fact you must memorise.

Relationship Logic

The question states that current increases while voltage stays the same. Using V = IR (or R = V / I ), if the current goes up, the resistance must have decreased.

Sentence Completion

...the resistance of the whisk decreases.

Topics

Physics · P1: Energy · P2: Electricity

Question and mark scheme from the AQA GCSE Combined Science: Trilogy examination, Physics Paper 1 (Foundation), 2024. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.