AQA AS Level Mathematics Paper 1, June 2025: Question 14

1 mark · Easy difficulty · Short Answer

Calculate the acceleration of a 2 kg particle subjected to a single horizontal force of 5 N.

Practise this question

Question

Question 14 asks: 'A particle of mass 2 kg is moving on a smooth horizontal surface under the action of a single horizontal force of 5 N. Find the acceleration of the particle. Circle your answer.' Four options are given horizontally: 0.4 m s⁻², 2.5 m s⁻², 10 m s⁻², and 24.5 m s⁻².
Question text

14 A particle of mass 2 kg is moving on a smooth horizontal surface under the action of a

single horizontal force of 5 N

Find the acceleration of the particle.

Circle your answer.

[1 mark]

0.4 m s–2 2.5 m s–2 10 m s–2 24.5 m s–2

Mark scheme

Show the mark scheme Mark scheme table for Question 14 showing marking instruction 'Circles second answer', AO '1.1b', mark 'B1', and typical solution '2.5 m s⁻²'.

Q Marking instructions AO Marks Typical solution

14 Circles second answer 1.1b B1 2.5 m s–2

Question 14 Total 1

How to answer it

Calculating Acceleration Using Newton's Second Law

📌 What this question tests

This question assesses basic understanding of Newton's Second Law of Motion ( F = ma ) in a 1D horizontal context with negligible resistance ("smooth surface"). It tests your ability to correctly rearrange the formula to find acceleration and avoid common arithmetic slips or unit misconceptions.

Question 14

Multiple Choice: Acceleration from a Single Horizontal Force [1 Mark]

✅ Correct Answer

2.5 m s⁻²

The student must circle the second option: 2.5 m s⁻² .

Mark Scheme Breakdown:
• B1 (AO 1.1b): Correct answer circled unambiguously.

📐 Step-by-Step Calculation

  1. Identify given values:
    Mass, m = 2 kg
    Resultant horizontal force, F = 5 N
  2. Recall Newton's Second Law:
    F = ma
  3. Rearrange for acceleration (a):
    a = F / m
  4. Substitute and solve:
    a = 5 / 2 = 2.5 m s⁻²

💡 Key Knowledge

  • Smooth surface: Means friction is zero ( F_friction = 0 N ), so the single applied force of 5 N is the net horizontal force.
  • Standard SI Units: Force in Newtons (N), mass in kilograms (kg), acceleration in metres per second squared (m s⁻²).
  • Directionality: Since motion is horizontal, vertical forces (weight W = mg and normal reaction R ) balance perfectly ( R = 2g ), having no effect on horizontal acceleration.

🧠 Exam Technique & Multiple Choice Strategy

  • Unambiguous circling: Ensure only one option is clearly circled. If you make a mistake, cross out the incorrect choice clearly and write your intended answer next to it.
  • Quick check: As this is a 1-mark opening question in Mechanics, it should take under 45 seconds. Do not overcomplicate it by introducing gravity into the horizontal direction.

❌ Common Errors & Distractor Breakdown

Examiners deliberately select common calculation traps as distractors:

Option Trap / Error Type How it happens
0.4 m s⁻² Inverted formula Dividing mass by force ( m / F = 2 / 5 = 0.4 ) instead of force by mass.
2.5 m s⁻² Correct F / m = 5 / 2 = 2.5
10 m s⁻² Multiplication instead of division Multiplying mass and force together ( m × F = 2 × 5 = 10 ).
24.5 m s⁻² Incorrectly including gravity ( g ) Multiplying force by g and dividing by mass: (5 × 9.8) / 2 = 24.5 . Gravity acts vertically, not horizontally!

Topics

Mechanics · R: Forces and Newton’s laws

Question and mark scheme from the AQA AS Level Mathematics examination, Paper 1, June 2025. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.