Why is a thin sheet of paper or cardboard sufficient to shield against alpha (α\alphaα) radiation?
Alpha particles have low penetrating power and are easily absorbed by thin materials.
Paper chemically reacts with alpha particles to neutralize them.
Cardboard decreases the half-life of alpha-emitting isotopes.
Thin materials reflect alpha particles back towards the radioactive source.
134 exam-style questions on CIE IGCSE Physics 5.2.2a Alpha, beta and gamma emission. Each one has a worked solution and a mark scheme showing where the marks go.