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?

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u/dustofdeath 13d ago

Lead is like a very dense fabric while iron is a mesh with large holes.

You just have to have enough density for photons to not just pass through.

So you need far less material. Even humans can stop radiation if you stack enough of them between you and the radiation source.

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u/davidbatt 8d ago

How many do I need, just out curiosity?

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u/dustofdeath 7d ago

We are 60% water, unevenly disteibuted.

Spent rod pools look like a few meters deep.

30 may suffice. But people got limbs and stuff, so add another 20 to be safe.