AQA GCSE Combined Science: Trilogy Physics Paper 2 (Foundation), 2022: Question 3

7 marks · Low Demand difficulty · Short Answer

Identify force directions and calculate weight and time for a hanging and falling apple using provided equations and Newton's laws.

Practise this question

Question

The image shows a multi-part physics question about an apple hanging from a tree. Figure 4 depicts an apple with an 'X' at its centre of mass. The question asks to draw a weight arrow on the diagram, calculate weight using mass (0.150 kg) and gravity (9.8 N/kg) with a provided formula, select the correct resultant force for a stationary and accelerating apple from multiple-choice options, and calculate fall time using change in velocity (4.9 m/s) and acceleration (9.8 m/s²) with a provided formula.
Question text

03 Figure 4 shows an apple hanging from a tree.

The X marks the centre of mass of the apple.

Figure 4

03.1 Draw an arrow on Figure 4 to represent the weight of the apple.

[1 mark]

03.2 The apple has a mass of 0.150 kg

gravitational field strength = 9.8 N/kg

Calculate the weight of the apple.

Use the equation:

weight = mass × gravitational field strength

[2 marks]

9 Weight = N

03.3 The apple in Figure 4 is stationary.

Why is the apple stationary?

[1 mark]

*08* Tick ( ) one box.

The resultant force on the apple is downwards.

The resultant force on the apple is upwards.

The resultant force on the apple is zero.10

When the apple is ripe it falls from the tree and accelerates towards the ground.

03.4 Why does the apple accelerate?

[1 mark]

Tick ( ) one box.

The resultant force on the apple is downwards.

The resultant force on the apple is upwards.

The resultant force on the apple is zero.

03 5 The acceleration of the apple is 9.8 m/s2

.

The velocity of the apple changes from 0 to 4.9 m/s

Calculate the time taken for the apple to fall to the ground.

Use the equation:

change in velocity

time taken =

acceleration

[2 marks]

Time taken = s

Mark scheme

Show the mark scheme The mark scheme provides answers for five sub-questions. 03.1 requires a vertical downward arrow from X. 03.2 shows the calculation 0.150 times 9.8 equals 1.47 Newtons. 03.3 identifies the resultant force as zero for a stationary apple. 03.4 identifies the resultant force as downwards for an accelerating apple. 03.5 shows the calculation 4.9 divided by 9.8 equals 0.5 seconds. Each calculation is worth 2 marks, and the other parts are 1 mark each, totaling 7 marks.

Question 3

AO /

Question Answers Extra information Mark

Spec. Ref.

03.1 vertical arrow from X pointing ignore any labels 1 AO2

downwards 6.5.1.3

AO /

Spec. Ref.

03.2 W = 0.150 × 9.8 1 AO2

6.5.1.3

W = 1.47 (N) allow 1.5 (N) 1

AO /

Spec. Ref.

03.3 the resultant force on the apple 1 AO1

is zero 6.5.4.2.1

AO /

Spec. Ref.

03.4 the resultant force on the apple 1 AO1

is downwards 6.5.4.2.2

AO /

Spec. Ref.

4.9

03.5 t = 1 AO2

9.8

6.5.4.1.2

t = 0.5 (s) allow 0.50 (s) 1

Total Question 3 7

How to answer it

Gravity, Weight, and Resultant Forces

What this question tests

This question assesses your understanding of weight as a force, how to use standard physics equations, and the relationship between resultant forces and motion (Newton's First and Second Laws).

Part 03.1

Drawing Force Vectors

Correct Answer

A vertical arrow starting from the X pointing directly downwards.

Exam Technique

Always use a ruler for force arrows. The arrow must start exactly on the 'X' (the centre of mass) to show where the force is acting from.

Key Knowledge

Weight is the force of gravity acting on an object. It always acts vertically downwards towards the centre of the Earth.

Part 03.2

Calculating Weight

Step-by-Step Calculation

  1. Identify the values: Mass = 0.150 kg, Gravitational field strength = 9.8 N/kg.
  2. Substitute into the equation: Weight = 0.150 × 9.8
  3. Calculate: Weight = 1.47 N
Award 1 mark for the correct substitution and 1 mark for the final answer.

Common Errors

  • Using the wrong units (Weight is in Newtons, Mass is in kg).
  • Rounding 1.47 incorrectly. The mark scheme allows 1.5 N, but 1.47 is more precise.
Parts 03.3 & 03.4

Resultant Forces and Motion

03.3 Stationary Apple

The resultant force on the apple is zero.

Reason: If an object is not moving (stationary), the upward force from the branch equals the downward weight. They cancel out.

03.4 Accelerating Apple

The resultant force on the apple is downwards.

Reason: To accelerate downwards, there must be an unbalanced force acting in that direction.

Examiner Insight

Students often confuse "forces acting on an object" with "resultant force". Even when stationary, gravity is still pulling the apple down, but the resultant (the total overall force) is zero because the branch pulls up with the same strength.

Part 03.5

Calculating Time from Acceleration

Step-by-Step Calculation

  1. Identify the values: Change in velocity = 4.9 m/s, Acceleration = 9.8 m/s².
  2. Substitute into the equation: time taken = 4.9 / 9.8
  3. Calculate: Time = 0.5 s
Award 1 mark for the substitution and 1 mark for the correct answer (0.5 or 0.50).

Key Knowledge: Acceleration

Acceleration is the rate of change of velocity. On Earth, objects in free-fall (ignoring air resistance) accelerate at approximately 9.8 m/s².

Topics

Physics · P5: Forces

Question and mark scheme from the AQA GCSE Combined Science: Trilogy examination, Physics Paper 2 (Foundation), 2022. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.