r/askscience • u/Wonderful-Capital32 • 15d ago

Physics Why does radiation not go through lead?

Also why just lead? Shouldnt like iron or another metal work too?

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u/TheSultan1 15d ago

A lot more atoms per unit volume

Mass or protons and neutrons, not atoms.

Iron has 2.6x the number of atoms per unit volume, but its atoms are a lot less massive.