An unstable nucleus can throw out three very different things: a heavy charged chunk, a tiny fast particle, or a burst of pure energy. Each ionises and penetrates matter to a different degree.
Alpha is a helium nucleus, beta is a fast electron, and gamma is electromagnetic radiation. Alpha is the most ionising but most easily stopped (by paper). Gamma is the least ionising but most penetrating (needs thick lead). Beta is in between, stopped by a few millimetres of aluminium.
Alpha is a helium nucleus, beta is a fast-moving electron, and gamma is electromagnetic radiation. Their ionising and penetrating powers run in opposite orders.
Alpha is the most ionising but least penetrating; gamma is the least ionising but most penetrating.
Put paper, aluminium and lead in the path and see which radiation gets through.
Four quick checks. Each correct answer earns XP and lights this skill on your star map.
An alpha particle is...
A beta particle is...
Gamma radiation is...
The most penetrating of the three radiations is...
The most ionising is the most easily stopped; the most penetrating ionises least.
| Radiation | Nature and how it is stopped |
|---|---|
| Alpha | A helium nucleus, most ionising, stopped by paper |
| Beta | A fast electron, stopped by a few millimetres of aluminium |
| Gamma | Electromagnetic radiation, least ionising, reduced by thick lead |
Ionising power and penetrating power run in opposite orders. Alpha ionises most but is stopped by paper, while gamma ionises least but passes through everything except thick lead. The most penetrating radiation is the least ionising.
Unlocks once the four checks above are done. Worth more XP, written in the style of Paper 2.
Which radiation is stopped by a sheet of paper?
Which radiation is the most strongly ionising?
A radiation passes through paper and a few millimetres of aluminium but is reduced only by thick lead. It is...
Alpha, beta and gamma are mapped. Keep the chain going.