A hospital changes its imaging procedure. Each patient has one investigation. The table shows doses from the procedure before and after the change.
| Quantity | Before | After |
|---|---|---|
| Dose to each patient in mSv | 2.0 | 1.5 |
| Dose to the worker per investigation in μSv\mu\mathrm{Sv}μSv | 2.0 | 1.0 |
| Investigations performed by the worker each day | 4 | 10 |
Which statement correctly evaluates the change?
Patient dose decreases by 25%25\%25%; the worker's daily dose increases by 25%25\%25%.
Patient dose decreases by 50%50\%50%; the worker's daily dose increases by 25%25\%25%.
Patient dose decreases by 50%50\%50%; the worker's daily dose decreases by 50%50\%50%.
Patient dose decreases by 25%25\%25%; the worker's daily dose decreases by 50%50\%50%.
97 exam-style questions on Edexcel GCSE Physics 6.5 Uses and dangers of radioactivity, covering 6.5.1 Uses of radioactivity, 6.5.2 Dangers of ionising radiation and precautions, 6.5.3 Half-life and radiation dangers, 6.5.4 Safety precautions for radiation exposure, and 6.5.5 Contamination and irradiation. Each one has a worked solution and a mark scheme showing where the marks go.