Question 1
A radioactive sample initially contains 1,600 atoms. After 3 half-lives have elapsed, the number of undecayed atoms remaining is
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Physics Β· Unit 1 Β· Ionising radiation and nuclear reactions Β· Nuclear model and stability
Solve radioactive decay problems using π = ππ (1 2)π and other arithmetic or graphical methods. Energy and mass defect
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Question 2
The graph shows the decay of two radioactive isotopes, P and Q, over time. What key feature allows isotope P to reach 25% of its original activity before isotope Q reaches 50% of its original activity?
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Question 3
A sample of technetium-99m initially contains 1,200 nuclei. After 24 hours, 75 nuclei remain. What conclusion can be drawn about the half-life of technetium-99m?
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Question 4
A medical isotope, Technetium-99m, has a half-life of 6.0 hours. A hospital receives a sample containing \(2.4 \times 10^{15}\) atoms of Technetium-99m at 8:00 am on Monday. Calculate the number of Technetium-99m atoms remaining in the sample at 8:00 pm on the same day. Show your working.
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