Which type of radiation is stopped by a sheet of paper?
Answer and explanation
Correct answer: D. Alpha particles
- Step 1: Alpha particles are heavily ionising but have very low penetrating power.
- Step 2: A sheet of paper or a few centimetres of air absorbs them.
Answer
Alpha particles.
Why not the others: Beta particles: need a few millimetres of aluminium to be stopped. Gamma rays: need thick lead or concrete to be reduced. X-rays: also need dense material to be absorbed.
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