It’s probably not a lead apron. For the reasons given. It’s a fairly heavy apron, for the reasons given, and it looks like they still sell lead aprons, and they used to sell tin, but the one your dentist is putting on you is probably an alloy with less than 1% lead.
You are getting into some unusual definitions of ‘stopping’ a photon. X rays get scattered by the electron cloud and ionize the atoms they hit and lose energy along the way. This leads to some energetic electrons kicking around, but ultimately what remains of the diminished energy X ray photon will probably be absorbed through photoelectric absorption and another electron flying around and falling back and emitting a photon of lower energy. Sure its’ energy still exists, but as an energetic electron bouncing around or residual lower energy photon. You could not point to or measure any specific remaining photon that was the original X-ray. It’s the same deal for the gamma rays (which are just higher energy photons) but with a few more collisions until the final absorption. So as all that is left of a gamma or x ray is a few energetic electrons bouncing around that will eventually calm down to a ground state and there is no trace of the original gamma or x-ray, so it is a reasonable thing to say that x rays or gamma rays can be ‘stopped’ .
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As we are talking about energy, a rib eye steak is a much better source of energy than a hamburger.
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A hamburger is just beef in its ground state.
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no?
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ok I’ll get my coat.
Huh. What are they made of?
Tin, antimony , tungsten bismuth. Anything dense.
I did a quick search for lead aprons to see what’s what. I clicked on a few links selling them. Despite the heading being “lead aprons” all the ones I saw were touted as lead-free. Sort of like plastic glasses or soy milk I guess.