AQA AS Level Physics Paper 2, November 2021: Question 35

1 mark · Easy difficulty · Multiple Choice

Identify the correct classification hierarchy of particles from the given tree diagrams.

Practise this question

Question

A multiple choice question asking which diagram shows the classification of particles. Four tree diagrams labeled A, B, C, and D present different hierarchical arrangements of particles, hadrons, leptons, baryons, and mesons. Below the diagrams are four option boxes labeled A, B, C, and D.
Question text

35 Which shows the classification of particles?

[1 mark]

A B

C D

A

B

C

D

Mark scheme

Show the mark scheme The mark scheme table indicating that option A is the correct answer, showing the diagram where particles branch into hadrons and leptons, and hadrons further branch into baryons and mesons.

A

How to answer it

Classification of Particles

What this question tests

This question assesses your knowledge of the Standard Model classification hierarchy for subatomic particles. You need to know how fundamental particle families (Hadrons and Leptons) branch out into further categories (Baryons and Mesons) based on their properties and quark composition.

Question 3.5 [1 mark

Particle Hierarchy Flowchart

Identifying the correct structural breakdown of subatomic particles

✅ Correct Answer: A

Option A correctly splits Particles directly into two primary groups: Hadrons and Leptons. It then correctly shows that Hadrons further subdivide into Baryons and Mesons.

💡 Key Knowledge

  • All particles experience either the strong nuclear force or not, dividing them into Hadrons (experience strong force) and Leptons (do not).
  • Hadrons are not fundamental; they consist of quarks and are split into Baryons (3 quarks) and Mesons (quark-antiquark pair).
  • Leptons are fundamental particles (e.g., electrons, neutrinos) and do not branch further into baryons or mesons.

🧠 Exam Technique

Work top-down through the tree diagrams provided in multiple-choice questions. Check the first branching level immediately: particles must split into Hadrons and Leptons, eliminating options B and C right away.

❌ Common Errors

  • Hierarchy inversion: Putting Baryons or Mesons at the top level above Hadrons (seen in options B and C). Remember that baryons and mesons are both types of hadrons.
  • Misplacing Leptons: Treating Leptons as a sub-branch under Hadrons (seen in option D). Leptons and Hadrons are distinct, parallel primary classifications of particles.
Mark Scheme Allocation: 1 mark awarded for selecting option A. (No consequential or partial credit for multiple-choice questions).

Topics

Physics · 3.2 Particles and radiation

Question and mark scheme from the AQA AS Level Physics examination, Paper 2, November 2021. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.