Lesson 3.2.1.7

3.2.1.7 Applications of conservation laws Quiz: AQA Physics, Unit 2

20 questions

Written by Revision Ninja · Last reviewed 11 October 2026

In partnership with Revision Ninja

Lesson 3.2.1.7, Applications of conservation laws: 20 multiple choice questions for the AQA Physics (7408), Unit 2: Particles and radiation, written with Revision Ninja.

Host it live on the board and students join with a game code on their own devices, or revise alone with Free Play. The answers are revealed in the game.

Host this setFree Play

The 20 questions

  1. Which quantity is conserved in every particle interaction?

    • strangeness only
    • the number of mesons
    • the number of quarks
    • electric charge

  2. In which interactions is strangeness conserved?

    • weak interactions only
    • strong and electromagnetic interactions
    • gravitational interactions only
    • weak and strong interactions only

  3. What change of strangeness can occur in a weak interaction?

    • always +1
    • 0, +1 or -1
    • +2 or -2 only
    • always -1

  4. Which quantities must be conserved in all particle interactions?

    • strangeness and baryon number
    • speed and spin
    • energy and momentum
    • mass and the number of particles

  5. In beta-minus decay, which quark change occurs?

    • a down quark changes to a strange quark
    • a down quark changes to an up quark
    • a strange quark changes to an up quark
    • an up quark changes to a down quark

  6. In beta-plus decay, which quark change occurs?

    • an up quark changes to a strange quark
    • an up quark changes to a down quark
    • a down quark changes to a strange quark
    • a down quark changes to an up quark

  7. What happens to the baryon number in beta-minus decay?

    • It increases by 1
    • It decreases by 1
    • It becomes zero
    • It is unchanged

  8. Is the reaction pi- + p to n + pi0 possible?

    • No, strangeness changes
    • No, baryon number is not conserved
    • No, charge is not conserved
    • Yes, charge, baryon number and strangeness are all conserved

  9. Which particle completes p to n + ? while conserving charge and baryon number?

    • e-
    • pi0
    • pi+
    • pi-

  10. Which interaction governs the decay K- to pi- + pi0?

    • weak interaction
    • gravitational interaction
    • strong interaction
    • electromagnetic interaction

  11. What is the lepton number of the antineutrino emitted in beta-minus decay?

    • +1
    • +2
    • 0
    • -1

  12. Which particle is emitted with the positron in beta-plus decay (p to n + e+ + ?)?

    • electron neutrino
    • W boson
    • electron antineutrino
    • photon

  13. A particle at rest with rest energy 1.02 MeV decays into two equal-energy photons. What is the energy of each photon?

    • 2.04 MeV
    • 0.51 MeV
    • 0.255 MeV
    • 1.02 MeV

  14. A neutral particle at rest decays into two particles, one moving to the right. What must the other particle do?

    • Move to the left with equal momentum
    • Move to the right with twice the momentum
    • Move to the right with equal speed
    • Remain at rest

  15. What is the missing particle in pi- + p to n + X?

    • electron
    • pi+
    • pi0
    • antiproton

  16. Why is the decay n to p + e- without an antineutrino forbidden?

    • Charge would not be conserved
    • The baryon number would change from 1 to 0
    • Energy would be created from nothing
    • The electron lepton number would change from 0 to +1

  17. Which conservation law led to the hypothesis of the neutrino in beta decay?

    • conservation of strangeness
    • conservation of mass number
    • conservation of charge
    • conservation of energy

  18. In beta-minus decay of 14 6 C, how does the number of down quarks change?

    • It decreases by 2
    • It increases by 1
    • It does not change
    • It decreases by 1

  19. What change in strangeness occurs in K+ to pi+ + pi0, and which interaction is involved?

    • Strangeness is unchanged and the interaction is strong
    • Strangeness changes by -1 and the interaction is weak
    • Strangeness changes by -2 and the interaction is weak
    • Strangeness changes by +1 and the interaction is strong

  20. Which quantity is NOT always conserved in a weak interaction?

    • electric charge
    • baryon number
    • lepton number
    • strangeness

All AQA Physics quizzes