After an accident at a nuclear power station, radioactive iodine-131 is released into the air.
Iodine-131 emits beta and gamma radiation. It has a half-life of 8 days.
People living near the power station are told to stay indoors with the windows closed.
Explain why.
Explain why the hazard from contamination by iodine-131 lasts longer than the hazard from being irradiated by a cloud of iodine-131 as it passes overhead.
Calculate the time taken for the activity of the iodine-131 to fall to 116\displaystyle \frac{1}{16}161 of its starting value.
Cows eat grass in the area around the power station. Milk from these cows is not drunk for several weeks after the accident.
Suggest why.
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.