The graph shows how the number of undecayed nuclei in a sample of a radioisotope prepared for medical imaging varies with time.
Activity is defined as the rate at which unstable nuclei decay. By drawing a tangent to the curve, determine the activity of the sample at t=4.0 hourst = 4.0\text{ hours}t=4.0 hours.
Give your answer in standard scientific notation to 2 significant figures, and state the appropriate SI unit.
Atoms and nuclear radiation Questions
Practise AQA GCSE Physics Atoms and nuclear radiation with exam-style questions for Foundation and Higher tier. 21 questions covering Radioactive decay and nuclear radiation, Nuclear equations, Half-lives and the random nature of radioactive decay, and Radioactive contamination, matched to the AQA GCSE Physics (8463) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.