Progressive Nuclear physics practice questions
Use Clevolab for progressive practice in nuclear physics. This page shows what the topic covers, what skills the current set targets, and a few real examples from the reviewed question bank.
About this topic
Clevolab treats nuclear physics as repeated practice with explanation, not just answer checking. This page is designed to make the topic legible before you open the app.
The current Progressive set covers radioactivity, decay, half-life, binding energy, and nuclear structure. 150 reviewed questions currently published for this page.
What you can practise
- Radioactive decay
- Half-life
- Nuclear equations
- Binding energy
- Nuclear structure
Real sample questions from the current set
These examples come from the reviewed questions currently stored for this topic. They are here so the page shows the actual flavour of Clevolab, not just a summary.
Sample question
Which particle is its own antiparticle?
- AElectronAnswer option
- BProtonAnswer option
- CPhotonCorrect answer
- DNeutrinoAnswer option
Why this answer is right
The photon is neutral and identical to its antiparticle. Electrons and protons have distinct antiparticles.
Antiparticles have opposite conserved quantum numbers. The photon has no electric charge, baryon number, or lepton number, and is identical to its antiparticle. Electrons have positrons as antiparticles; protons have antiprotons.
Sample question
After three half-lives, what fraction of a sample remains undecayed?
- A25%Answer option
- B6.25%Answer option
- C75%Answer option
- D12.5%Correct answer
Why this answer is right
Each half-life multiplies the remaining fraction by $1/2$. After three, the fraction is $(1/2)^3=1/8=12.5\%$.
Exponential decay gives $$N(t)=N_0\,2^{-t/T_{1/2}}.$$ After $n$ half-lives, $$\frac{N}{N_0}=2^{-n}.$$ For $n=3$, $$2^{-3}=1/8=0.125=12.5\%.$$ This applies equally to the number of undecayed nuclei or activity.
Sample question
At $e^+e^-$ energies between the $\phi$ and $J/\psi$, what is the expected value of $R=\sigma(e^+e^-\to\text{hadrons})/\sigma(e^+e^-\to\mu^+\mu^-)$ from quark charges and three colors?
- A1.0Answer option
- B1.5Answer option
- C2.0Correct answer
- D3.0Answer option
Why this answer is right
With $u,d,s$ active, $R=N_c\sum_f Q_f^2=3[(2/3)^2+(-1/3)^2+(-1/3)^2]=3\times(6/9)=2.0$.
In the parton model, $$R=N_c\sum_f Q_f^2,$$ where $N_c=3$ is the number of colors and the sum runs over open flavors.
How this page fits into Clevolab
Clevolab is broader than any one exam mode. GCSE and A-level pages are useful entry points, while the wider project is about sharpening understanding through repeated topic practice.