WJEC A Level Physics
WJEC A Level Physics 3.5 Nuclear Decay Exam Questions
Free WJEC A Level Physics exam questions on 3.5 Nuclear Decay, with mark schemes. Covers alpha, beta and gamma radiation, the decay law, half-life and activity.
3.5 Nuclear Decay exam questions
1 question pack of real past exam questions with its mark scheme. Answer every question without notes, then mark your answers line by line against the mark scheme.
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A Level Physics Flashcards
Every answer is written in mark scheme wording, so you learn exactly what examiners give marks for. Pick your exam board, then test yourself with the questions on this page.
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About WJEC A Level Physics 3.5 Nuclear Decay
This topic covers radioactive decay.
What you need to know
- Radiation types Properties of α, β and γ and their penetration.
- Decay equations Balancing nucleon and proton numbers.
- Decay law A = λN and N = N₀e^(−λt).
- Half-life T½ = ln2/λ.
Common mistakes in 3.5 Nuclear Decay
- Forgetting to correct for background count.
- Mixing activity and count rate.
- Using minutes and seconds inconsistently with λ.
Try three 3.5 Nuclear Decay exam-style questions
1. A sample has half-life 6.0 h. Find λ in s⁻¹. (1 mark)
Show the mark scheme answer
3.2 x 10⁻⁵ s⁻¹.
2. Write the decay of radium-226 by alpha emission. (1 mark)
Show the mark scheme answer
²²⁶₈₈Ra → ²²²₈₆Rn + ⁴₂He.
3. Explain why decay is random. (1 mark)
Show the mark scheme answer
It is impossible to predict which nucleus will decay next.
3.5 Nuclear Decay FAQs
What does Nuclear Decay cover?
Radiation types, the decay law and half-life.
Which practical links here?
Investigating absorption of radiation or modelling decay.
Why plot ln A against t?
It gives a straight line with gradient −λ.
Revise this topic with flashcards: A Level Physics Flashcards, with mark scheme answers for Anki and Quizlet.
