• db2@lemmy.world
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    1 day ago

    If they’re being launched by the same spring mechanism you’re better off with the bowling ball than a little glass bullet.

    • redlemace@lemmy.world
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      1 day ago

      Depends, how tight is the spring? At high velocity i’d guess a marble will penetrate the body, where at low velocity a marbel would be easier to stop

      • JayDee@lemmy.sdf.org
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        13 hours ago

        I think that spring still leaves ambiguity. A very thick, powerful spring like that in an ejection seat could probably get the bowling ball airborne, but wouldn’t actually impart anywhere near the same amount of energy on the marble.

        A small elastic band like that used in a slingshot on the other hand would have difficulty getting the bowling ball to fly at all but could turn the marble into a bullet.

      • deranger@sh.itjust.works
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        1 day ago

        I think they’ll both be exactly the same difficulty to stop due to conservation of energy. If the spring used is the same for both the bowling ball and the marble, the bowling ball is going to be going much, much slower than the marble.

        • mmddmm@lemm.ee
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          23 hours ago

          If we pretend people are homogeneous, both will penetrate through the same amount of “meat”. What means the bowling ball will carve something like a 0.1mm deep 30cm wide hole, while the marble will carve something like a 10cm deep 1cm wide hole.

        • JustAnotherKay@lemmy.world
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          1 day ago

          This feels wrong to my brain. Something that is much heavier must take more energy to move, and therefore to stop. The same velocity doesn’t necessarily imply the same amount of kinetic energy right? Now I gotta go look this up or wait for someone to tell me why I’m stupid

          • deranger@sh.itjust.works
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            1 day ago

            The spring imparts the same amount of energy to the marble and bowling ball. The two objects are not at the same velocity, the marble would be moving significantly faster.

            The same velocity doesn’t necessarily imply the same amount of kinetic energy right?

            Not at all.

            E = 1/2mv^2

            Since energy (E) is provided by the same spring in both cases, the energy of the bowling ball and the marble are equal. Since mass (m) is much higher for the bowling ball, the bowling ball’s velocity (v) must be significantly lower.

            • JustAnotherKay@lemmy.world
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              1 day ago

              That’s why I’m stupid! End of shift sleepy brain forgot about the parent comment talking about the spring because of the confusion about velocity. Seems so silly to forget a piece of the conversation while I’m having it, but this happens a lot. I really oughta get an ADHD diagnosis lol

        • RmDebArc_5@sh.itjust.works
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          1 day ago

          You also have to consider air resistance, that should reduce the energy of the bowling ball when hitting you, making it easier to stop

          • earphone843@sh.itjust.works
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            1 day ago

            Friction would be way more of a determining factor than air resistance, assuming they’re traveling along the ground.

          • deranger@sh.itjust.works
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            1 day ago

            Air resistance will affect the marble more since it’s traveling faster. I also feel like either mass (or more likely, density) of the object matters, which would advantage the bowling ball in this aspect too.

            Where are the physics nerds at, we need answers!

            • EddoWagt@feddit.nl
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              22 hours ago

              The bowling ball also has more mass compared to the surface area than the marble because maths, so air resistance would be very little for the bowling ball compared to the marble