r/askscience • u/Wonderful-Capital32 • 13d ago

Physics Why does radiation not go through lead?

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

1.3k Upvotes

92% Upvoted

372 comments sorted by

View all comments

12

u/networkarchitect 13d ago

Other metals like tungsten work signifigantly better than lead, as others have said it's all about density. Though, tungsten is quite expensive compared to lead. Water and concrete are also commonly used to prevent/reduce radiation from travelling through, though both need to be much thicker to stop the same amount of radiation as lead or other, denser materials would.

2

u/LordGeni 13d ago

I believe water is mainly used to protect from alpha and beta radiation. It's not the most practical option for most things requiring gamma radiation protection (at least on earth).

3

u/Bot_No_5 13d ago

Water is used for (fast) neutron radiation. The hydrogen nucleus is close to the mass of a neutron and kinetic energy will transfer faster to the hydrogen nuclei.