A radioactive isotope has a half-life of 20 days. After 60 days, what fraction of the original sample remains undecayed?

Question

Think Extraordinary · Accepted Answer

Correct Answer: Option A. 1/8 (12.5%). Explanation: Number of half-lives n = t / T₁/₂ = 60 / 20 = 3. Remaining fraction N / N₀ = (1/2)³ = 1/8.

Answer

Option B: 1/4 (25%)

Answer

Option C: 1/16 (6.25%)

Answer

Option D: 1/2 (50%)

Modern Physics - Nuclear