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[–] 11 points 1 day ago (3 children)

Yet 2 meters of water will stop neutrons. Water is pretty cool.

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  • [–] 5 points 1 day ago (2 children)

    Sure, but just because it's chock full of Hydrogen, which happens to be about the same mass as a neutron and thus takes up a lot of its energy per collision. Plastic, being a hydrocarbon, does the same thing.

    That being said, water is pretty cool. You could use 2 inches of lead to stop 90% of gamma radiation, or 2 feet of water for the same effect. On top of that, metal is terrible at slowing neutrons (due to metal not being hydrogen), but that same 2 feet of water will slow down the neutrons by about 99.5%.

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  • [–] 3 points 1 day ago*

    Hydrogen's cool man. It's just like, one little proton out there in the universe, with his Jiminy Cricket Electron buddy circling around all times, making sure he stays balanced. An unfathomable number of them, more than anything else. All exactly the same yet repelled by each other, like speed dating at comic-con.

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  • [–] 85 points 2 days ago (2 children)

    Tell me more about how you're unstable, full of bugs and need to finish your development

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  • [–] 9 points 2 days ago*

    And they're so insanely positive all the time that they can rip the negativity out of you twice in such a way that it scrambles your DNA.

    Never underestimate the toxic positivity of an alpha particle...

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  • [–] 31 points 2 days ago (2 children)

    And, from the "size really doesn't matter that much" faction, the neutrino just arrived...

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  • [–] 24 points 2 days ago (1 child)

    Tbf you actually want 0 penetration. Its already a hole, you just want to insert yourself into said preexisting hole.

    Making a new one is probably a bad idea

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  • [–] 16 points 2 days ago (4 children)
  • [–] 17 points 2 days ago (3 children)

    What prevents Superman from being able to see through lead but not concrete?

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  • [–] 19 points 2 days ago (2 children)

    If you're talking about the neutron it's because concrete has a lot of hydrogen. Alpha particles, beta particles, and light (gamma rays in this picture) interact with electrons, with the probability of being stopped increasing with electron density. Lead has a lot of electrons (its lower on the periodic table, called a "high z" element).

    Neutrons, however, don't care about electrons and instead interact with the nucleus, with the probability of being stopped depending on the spin state of the nucleus and the neutron. This doesn't follow a specific pattern on the periodic table, but hydrogen has a big chance of interacting with the neutron while lead doesn't. Cadmium, boron, and I think lithium 7 also would stop neutrons easily (there are more of course but those are what I remember offhand).

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  • [–] 7 points 2 days ago (2 children)

    Nah, that's not what they're talking about. Superman's vision is capable of penetrating concrete, but gets reliably stopped by lead. None of the particles here (or, I'm guessing, anywhere) have that property.

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  • [–] 4 points 2 days ago

    Yeah! Well if i get inside your body 🥵 (IF) I can rip your DNA to shreds unlike any of those other beta or gamma particles 😤

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  • Well, duh. Did you not notice the blonde constantly chasing him?

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  • [–] 3 points 2 days ago (2 children)

    Aren't Gamma-Rays impossible to stop even with lead? You can only weaken them.

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  • [–] 8 points 2 days ago*

    Gamma rays are stopped by things with a lot of electrons, so a sufficiently thick block of lead will stop it

    EDIT: higher energy light has more penetration power (so gammas are quire penetrating), but it's a finite value

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  • [–] 2 points 2 days ago

    How much concrete do you actually need to stop a neutron with probability 1/2? Is 1 lightsecond enough?

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  • [–] 1 point 2 days ago
    [+] 1 point 2 days ago
    [–] 1 point 2 days ago

    Neutron Male don't interact with nuthin'.

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