Answer: lambda N(t).
- A lambda N(t)
- B lambda/N(t)
- C N(t)/lambda
- D lambda²N(t)
Correct answer: A. lambda N(t)
Explanation: Activity A = |dN/dt| = lambda × N(t). Activity is proportional to number of undecayed nuclei.
Binding energy per nucleon rises sharply for light nuclei, peaks around iron-56 (the most stable nucleus), then slowly declines for heavier nuclei - which is exactly why fusing light nuclei or splitting heavy nuclei both release energy: each moves the products toward this stability peak.
Concept context
Radioactivity, nuclear reactions, fission, fusion, and binding energy.