AQA GCSE Combined Science: Trilogy Physics Paper 1 (Foundation), 2024: Question 5

11 marks · Standard Demand difficulty · Short Answer

Explain thermal conductivity, describe gas particle behavior and pressure-temperature relationships, and calculate volume and mass using the density equation.

Practise this question

Question

A multi-part physics question regarding a large cylindrical metal container used for cooling data-storage computers in the sea. It includes a diagram of the container with a person for scale, a particle diagram showing six circles in a regular arrangement representing a solid, and a blank box for drawing gas particles. The text asks about thermal conductivity, gas pressure mechanisms, the effect of temperature on particle speed and pressure, and concludes with calculations for volume and mass using given dimensions and density.
Question text

05 Data-storage computers get very hot.

Scientists investigated using the sea to cool data-storage computers.

The computers were set up inside a large metal container.

Figure 8 shows the metal container before it was lowered into the sea.

Figure 8

05.1 Why is the container made of metal?

[1 mark]

Tick ( ) one box.

Metal has a high thermal conductivity.

Metal is a good thermal insulator.

Metal is a poor conductor of thermal energy.21

05.2 The walls of the container are solid.

Figure 9 shows an arrangement of six particles in a solid.

Figure 9

The air inside the container is a gas.

Draw an arrangement of six particles in a gas in the box below.

[1 mark]

05.3 How does the air in the container exert pressure on the container?

[1 mark]

Tick ( ) one box.

Air particles absorb energy from the container.

Air particles collide with the walls of the container.

Air particles expand to fill the container.22

05.4 As the container is lowered into the sea, the temperature of the air in the

container decreases.

Complete the sentence.

Choose the answer from the box.

[1 mark]

decreases stays the same increases

When the temperature of the air in the container decreases, the average speed of the

air particles .

05.5 After the temperature of the air in the container had decreased, the computers were

switched on.

The computers caused the temperature of the air to then increase.

Describe how the air pressure in the container changed as the temperature decreased

and then increased.

[2 marks]

05.6 The container has a length of 12 m.

The container has a cross-sectional area of 7.5 m2.

Calculate the volume of the container.

Use the equation:

volume = length × cross-sectional area

[1 mark]

Volume = m3

Use the Physics Equations Sheet to answer questions 05.7 and 05.8.

05.7 Write down the equation that links density (ρ), mass (m) and volume (V).

[1 mark]

05.8 The average density of the container and its contents is 1100 kg/m3.

Calculate the mass of the container and its contents.

Use your answer to Question 05.6

[3 marks]

Mass = kg

Mark scheme

Show the mark scheme The mark scheme for question 5, showing a total of 11 marks. It specifies 'metal has a high thermal conductivity' for 5.1, a diagram of 6 spread-out particles for 5.2, 'air particles collide with the walls' for 5.3, and 'decreases' for 5.4. For 5.5, it awards 2 marks for stating pressure decreases then increases. Calculations show volume as 90 m3, the density formula (mass/volume), and a final mass calculation of 99,000 kg with error carried forward allowed.

Question 5

AO /

Question Answers Extra information Mark

Spec. Ref.

05.1 metal has a high thermal 1 AO1

conductivity 6.1.2.1

AO /

Spec. Ref.

05.2 6 particles all spread apart 1 AO1

irregularly within the box 6.3.1.1

e.g.

AO /

Spec. Ref.

05.3 air particles collide with the walls 1 AO1

of the container 6.3.3.1

AO /

Spec. Ref.

05.4 decreases – – 1 – AO1

6.3.3.1

AO /

Spec. Ref.

05.5 (the pressure) decreased as 1 AO1

temperature decreased 6.3.3.1

(the pressure) increased as 1

temperature increased

allow 2 marks for it decreased

then increased 15

AO /

Spec. Ref.

05.6 90 (m3) 1 AO2

6.3.1.1

AO /

Spec. Ref.

05.7 mass 1 AO1

density =

volume 6.3.1.1

or

m

𝜌 =

V

AO /

Spec. Ref.

m 1

05.8 1100 = allow ecf from question 05.6 AO2

6.3.1.1

mass = 90 × 1100 1

99 000 (kg) 1

Total Question 5 11

How to answer it

Particle Model and Density of a Submerged Container

What this question tests

This question assesses your understanding of thermal conductivity, the particle model of gases, the relationship between temperature and pressure, and your ability to perform volume and density calculations.

Part 05.1

Thermal Properties of Metals

Correct Answer

Metal has a high thermal conductivity.

Key Knowledge

Thermal conductivity is a measure of how quickly energy is transferred through a material by conduction. Metals are excellent conductors because they have free electrons.

Exam Technique

The context is cooling the computers. To cool something down, you want heat to escape quickly. Therefore, you need a material that conducts heat well, not an insulator.

Part 05.2

Drawing Gas Particles

Correct Answer

Draw 6 circles spread far apart and arranged randomly within the box. None of the circles should be touching.

Common Errors

  • Drawing the wrong number of particles (the question specifies six).
  • Drawing particles in a regular pattern (that's a solid).
  • Drawing particles touching (that's a liquid or solid).
Parts 05.3 & 05.4

Gas Pressure and Temperature

Correct Answers

05.3: Air particles collide with the walls of the container.

05.4: Decreases.

Key Knowledge

  • Pressure is caused by particles hitting the surfaces of their container, exerting a tiny force with every collision.
  • Temperature is a measure of the average kinetic energy (speed) of the particles. If temp goes down, speed goes down.
Part 05.5

Describing Pressure Changes

Correct Answer

The pressure decreased as the temperature decreased, and then the pressure increased as the temperature increased.

1 mark for decrease, 1 mark for increase.

Examiner Insight

Top-level responses clearly linked the pressure change to the temperature change in two distinct steps. If you just wrote "it decreased then increased" without mentioning temperature, you still get the marks here, but it is better practice to be specific.

Part 05.6

Calculating Volume

Step-by-Step Calculation

  1. Identify values: Length = 12 m, Area = 7.5 m²
  2. Use formula: Volume = 12 × 7.5
  3. Result: 90 m³
Parts 05.7 & 05.8

Density and Mass

05.7: The Equation

density = mass / volume

Or using symbols: ρ = m / V

05.8: Step-by-Step Mass Calculation

  1. Substitute known values into the equation:
    1100 = mass / 90
  2. Rearrange to find mass:
    mass = 1100 × 90
  3. Calculate final answer:
    mass = 99,000 kg

Error Carried Forward (ecf)

If you got the volume wrong in 05.6, use your wrong answer here! The examiner will still give you full marks for 05.8 if your calculation is correct based on your previous mistake.

Calculation Traps

Don't forget the units! While not required for the mark here (as they are provided), always check if you need to convert grams to kilograms or cm³ to m³ in other questions.

Topics

Physics · P1: Energy · P3: Particle Model of Matter

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.