IB skill practice

Calculate activity and decay constants

Paper 1, Paper 2 5 marks Difficulty 3

Decay constant from half-life

In a second version of the same nuclear physics investigation, a radioisotope in a radiation safety practical has half-life \(9\,\text{h}\). Calculate its decay constant in units of \(10^{-5}\,\text{s}^{-1}\). Use the diagram first, then calculate the requested value. Enter the numerical result and choose the interpretation that matches the nuclear physics meaning.

Worked practice: physics data and result

Read the physical quantities first, then calculate the result and state what it means.