• pikmeir@lemmy.world
    link
    fedilink
    English
    arrow-up
    241
    ·
    6 months ago

    For anyone wondering it’s because the bowling ball slightly pulls the earth faster toward itself. This amount is too small to possibly measure. But imagine if the bowling ball were the size of another Earth and it’s easier to see why it happens.

    • nova_ad_vitum@lemmy.ca
      link
      fedilink
      English
      arrow-up
      49
      arrow-down
      2
      ·
      6 months ago

      This amount is too small to possibly measure

      What the fuck did you say to me you little bitch? I’m going to go get $300 million in funding to create a device so complex and so sensitive that a butterfly sneezing 30 miles away will fuck it up and then I’m going to directly measure the the acceleration of the earth as a result of the mass of that bowling ball. You fucked up, kiddo.

      • Average metrologist, probably
      • Tlaloc_Temporal@lemmy.ca
        link
        fedilink
        English
        arrow-up
        5
        ·
        6 months ago

        The issue isn’t so much the sensitivity (although that is a significant issue), it’s all the other crap going on. You’ll probably be able to filter out the Mains Hum, but every anything moving in the same axis as the test will confount the data.

        I’m thinking we might set up the instuments near counterweight energy storage or pumped hydro, and some on the exact opposite side of the planet, and try to measure the movement of the earth that way.

        We can already see a change in the length of a day after big earthquakes and dam construction/destruction, but I don’t think the acceleration has ever been measured directly.

      • bort
        link
        fedilink
        English
        arrow-up
        14
        ·
        6 months ago

        because of two bodies can not occupy the same space, the feather and the ball will be in different position when you drop them. And therefor gravitation will pull the earth slightly more toward the ball and slightly less toward the feather.

    • KazuchijouNo@lemy.lol
      link
      fedilink
      English
      arrow-up
      9
      arrow-down
      4
      ·
      6 months ago

      But being more massive means that due to inertia the ball will take just a tiny little wee bit longer to start moving no? So they end up falling at the same time.

      Also, are these Newtonian mechanics? How do they compare to relativity at the “bowling ball and feather” scale?

      Someone please correct me if I’m wrong. It’s been a while since I read anything physics-related.

        • KazuchijouNo@lemy.lol
          link
          fedilink
          English
          arrow-up
          5
          arrow-down
          2
          ·
          6 months ago

          Oh yes! I omitted that part, but what I meant to say is that mass and inertia balance each other, so that in the end the acceleration from gravity ends up the same for any object.

          • Tlaloc_Temporal@lemmy.ca
            link
            fedilink
            English
            arrow-up
            2
            ·
            6 months ago

            The bowling ball will still pull the Earth more. For us, everything accelerates at 9.8m/s² (because we all fall to the same Earth), but the Earth accelerates differently per attracting object.

      • qjkxbmwvz@startrek.website
        link
        fedilink
        English
        arrow-up
        6
        ·
        6 months ago

        The above is just referring to the fact that the standard “feather vs. bowling ball” question assumes the earth/moon/ground is immovable. In that case, Newton says they fall the same.

        The fact that the ground is not immovable is what’s being referenced — in this picture, things don’t “fall,” they are each accelerated towards each other.

  • brown567@sh.itjust.works
    link
    fedilink
    English
    arrow-up
    104
    ·
    6 months ago

    This is fascinating! Both of them accelerate toward the earth at the same rate, but because of the bowling ball’s greater mass, the EARTH accelerates faster toward the bowling ball than it does toward the feather, so it’s imperceptibly faster XD

    • chicken@lemmy.dbzer0.com
      link
      fedilink
      English
      arrow-up
      27
      arrow-down
      2
      ·
      6 months ago

      But they are being dropped at the same time for dramatic effect, so the earth will also be accelerating towards the feather at bowling ball speeds because the feather is next to the bowling ball, therefore they still land at the same time.

      • Dwomen@lemmy.dbzer0.com
        link
        fedilink
        English
        arrow-up
        33
        arrow-down
        1
        ·
        6 months ago

        That’s only be true if the feather was in the same position as the ball. Otherwise, the earth is moving ever so slightly more towards the ball.

        • mexicancartel@lemmy.dbzer0.com
          link
          fedilink
          English
          arrow-up
          6
          ·
          6 months ago

          You are forgetting the sun. The earth turns in the direction of sun ever so slightly so if you align the feather next to the ball in the side of the sun, then probably the feather falls faster

        • dumbass@leminal.space
          link
          fedilink
          English
          arrow-up
          5
          ·
          6 months ago

          So, what you’re saying is, to do this experiment correctly, we have to stop the earth from moving. . I’m keen.

      • aname@lemmy.one
        link
        fedilink
        English
        arrow-up
        10
        ·
        6 months ago

        No, because the earth is accelerating towards the bowling ball and the feather is next to the bowling ball, the force vector is (ever so slightly) greater towards the bowling ball than the feather, thus the bowling ball drops faster

        • chicken@lemmy.dbzer0.com
          link
          fedilink
          English
          arrow-up
          1
          ·
          6 months ago

          Yeah I thought about it and I guess I’m wrong. I thought that maybe the ball still wouldn’t be faster if there was a perfectly flat surface for both objects to land on, but I imagined how it would be if the bowling ball and feather were actually very far apart, and of course they wouldn’t be travelling perpendicular to the platform, and the path of the feather would follow more of a curve. So a slight distance would be the same thing just less.

  • Granixo@feddit.cl
    link
    fedilink
    English
    arrow-up
    34
    arrow-down
    18
    ·
    6 months ago

    It’s not even because it’s heavier, it’s because it’s way more dense.

    • shutz@lemmy.ca
      link
      fedilink
      English
      arrow-up
      61
      ·
      6 months ago

      It’s not density, it’s mass. A mass of 1kg compressed to the density of the Sun’s core would pull the Earth with just as much force as a 1kg ball of styrofoam.

      • rockerface 🇺🇦@lemm.ee
        link
        fedilink
        English
        arrow-up
        20
        ·
        6 months ago

        And is the Sun was replaced with a black hole of the same mass, the Earth would just keep on rotating around it without issues, if slightly frozen

        • chatokun@lemmy.dbzer0.com
          link
          fedilink
          English
          arrow-up
          6
          ·
          6 months ago

          Xkcd did a what if on a black hole moon (getting it to collapse into one may be impossible, but a black hole the mass of the moon is theoretically stable), and it has the same conclusion, except just slightly colder instead of slightly frozen. And by slightly, I mean almost imperceptible.

          https://what-if.xkcd.com/129/

      • Chrobin@discuss.tchncs.de
        link
        fedilink
        English
        arrow-up
        3
        ·
        edit-2
        6 months ago

        Just to add some formality to this, the original commenter might want to look up the shell theorem for classical mechanics and Birkhoff’s theorem for general relativity.

    • Carrolade@lemmy.world
      link
      fedilink
      English
      arrow-up
      21
      ·
      edit-2
      6 months ago

      The guy on the right, if he be so wise in the ways of science, should be using the word “massive” instead of “heavier”.

      • KillerTofu@lemmy.world
        link
        fedilink
        English
        arrow-up
        10
        ·
        edit-2
        6 months ago

        Heavy is a subjective term based on the force of gravity. You are heavier if we weigh you on the earth compared to if you are weighed on the moon.

        Your mass in those two examples is unchanged. The amount of mass you have is finite and not subjective like weight.

      • Granixo@feddit.cl
        link
        fedilink
        English
        arrow-up
        1
        arrow-down
        4
        ·
        6 months ago

        The feather clearly has a more aerodynamic shape, thus, it wouldn’t fall as fast as a sphere with the same weight.

  • JohnDClay@sh.itjust.works
    link
    fedilink
    English
    arrow-up
    12
    ·
    6 months ago

    Does the bowling ball ever so slightly increase the gravitational constant because of it’s greater mass? Is that what the right guy is getting at?

    • dream_weasel@sh.itjust.works
      link
      fedilink
      English
      arrow-up
      38
      ·
      edit-2
      6 months ago

      The gravitational constant G, no, the mutual gravitational force between the earth and the ball approximated as g, yes.

      Edit: Since this is a little pedantic, G is used to calculate g.

      • Faresh@lemmy.ml
        link
        fedilink
        English
        arrow-up
        7
        ·
        edit-2
        6 months ago

        But how would that make the bowling ball fall faster? F = G × m₁ × m₂ / r² and F = m₁ × a ⇒ a = F / m = G × m₂ / r², where m₁ is the mass of the ball and m₂ the mass of the planet. So the gravitational acceleration of a bowling ball is independent of its mass (assuming the planet has way more mass than a bowling ball).

        • Patapon Enjoyer@lemmy.world
          link
          fedilink
          English
          arrow-up
          18
          ·
          edit-2
          6 months ago

          I guess the bowling ball attracts the Earth towards it, shortening the distance so it hits the ground faster

    • hddsx@lemmy.ca
      link
      fedilink
      English
      arrow-up
      5
      ·
      6 months ago

      No. F=GMm/d2. The mass of the earth doesn’t change so g=GM/d2 will not change

      • Tar_Alcaran@sh.itjust.works
        link
        fedilink
        English
        arrow-up
        8
        ·
        6 months ago

        Ah but the earth doesn’t just attract the ball or feather. The bowling ball attracts the earth as well, and since it has more mass, it will pull the earth towards it faster than the feather.

        But if you drop them at the same time, that’s moot.

        • hddsx@lemmy.ca
          link
          fedilink
          English
          arrow-up
          3
          ·
          6 months ago

          In other words, the feather and ball are both attracted to the earth at the same rate but because the ball has a higher mass, the earth is very slightly more attracted to the ball

      • JohnDClay@sh.itjust.works
        link
        fedilink
        English
        arrow-up
        6
        ·
        6 months ago

        So why does the bowling ball fall faster in a vacuum? Does it appear faster locally because the heavier object makes local time slower than the lighter object compared to a distant observer? I’m trying to understand what the meme is getting at.

        • dev_null@lemmy.ml
          link
          fedilink
          English
          arrow-up
          2
          ·
          6 months ago

          Because it, ever so slightly, pulls Earth towards it with it’s own, miniscule gravity.

          • JohnDClay@sh.itjust.works
            link
            fedilink
            English
            arrow-up
            3
            ·
            6 months ago

            But that doesn’t make the bowling ball fall faster to a distant observer, just the earth fall twords the ball. To an observer on earth it would appear to fall faster though.

  • Heavybell@lemmy.world
    link
    fedilink
    English
    arrow-up
    11
    arrow-down
    1
    ·
    6 months ago

    There’s a video of astronauts doing the heavy thing vs feather in vacuum experiment. I think it was a hammer rather than a bowling ball tho.

  • mako@lemmy.today
    link
    fedilink
    English
    arrow-up
    9
    ·
    6 months ago

    I get that the heavier bowling ball affects the acceleration of the earth more than the lighter feather, but I don’t see how that means it’s falling faster as the meme is stating. The bowling ball would meet the earth first when dropped separately and from the same height because the earth is (imperceivably) accelerating toward it faster than it does the falling feather, but both the bowling ball and feather are falling at the same rate due to Earth’s gravitational force.

    Or am I missing something?

    • Adalast@lemmy.world
      link
      fedilink
      English
      arrow-up
      14
      arrow-down
      1
      ·
      6 months ago

      One definition for a “rate of falling” would comfortably be “the time it takes the surfaces of two free gravitational separated by some distance to meet.” With this in mind, the imperceptible but very real difference in the acceleration of the earth towards the bowling ball would become part of that equation, as it shortens the distance between the two from the other side.

      Think of it like a head on collision of two vehicles. You can do the math as two bodies colliding with opposite velocity vectors, or you can arrive at the same mathematical result (at least for some calculations) by considering one of them to be stationary and the other to have the sum of the two speeds in the direction of its original velocity. “Two cars colliding head on at 60mph is the same as one car hitting a brick wall at 120mph.” It is rough and doesn’t work for all calculations, but the idea is the same.

        • Adalast@lemmy.world
          link
          fedilink
          English
          arrow-up
          3
          ·
          6 months ago

          Yeah, that’s why I used the heavy caveats. The wall produces an inelastic collision which will do WAY more damage as all of the energy is arrested rather than an elastic collision of the two vehicles in which a good portion of energy is spread between the two bodies as they separate.

      • bouh@lemmy.world
        link
        fedilink
        English
        arrow-up
        1
        ·
        6 months ago

        Well, considering the scales, the difference is not only imperceptible, I’m pretty sure it’s impossible to measure.

  • iceonfire1@feddit.nl
    link
    fedilink
    English
    arrow-up
    10
    arrow-down
    2
    ·
    6 months ago

    I think the answer to this question changes based on your interpretation of ‘falling faster’. I.e. whether that refers to the total time between the start and end of the fall or to the speed of the feather/ball to an outside observer.

  • Thunderwolf@lemmy.world
    link
    fedilink
    English
    arrow-up
    2
    arrow-down
    10
    ·
    edit-2
    6 months ago

    I haven’t seen anyone mention this yet, so here’s how I understand it. The feather falls slower in non-vacuum conditions because it reaches its terminal velocity much more quickly than the bowling ball.

    Edit: terminal velocity: https://en.m.wikipedia.org/wiki/Terminal_velocity

    Also edit: https://ucscphysicsdemo.sites.ucsc.edu/physics-5a6a/coin-and-feather/#:~:text=Because the feather has a,small%2C the feather falls slowly.

      • Thunderwolf@lemmy.world
        link
        fedilink
        English
        arrow-up
        1
        ·
        6 months ago

        I imagine terminal velocity with no air resistance would be 9.8m/s/s. I was saying that the feather reaches terminal velocity more quickly than a bowling ball in non-vacuum conditions

        • 0ops@lemm.ee
          link
          fedilink
          English
          arrow-up
          4
          ·
          6 months ago

          9.8 m/s/s is acceleration due to gravity, not a velocity, or its units would be m/s

        • Shareni@programming.dev
          link
          fedilink
          English
          arrow-up
          1
          ·
          6 months ago

          Terminal velocity is the maximum speed attainable by an object as it falls through a fluid (air is the most common example). It is reached when the sum of the drag force (Fd) and the buoyancy is equal to the downward force of gravity (FG) acting on the object. Since the net force on the object is zero, the object has zero acceleration

          Objects in a vacuum have no drag and no terminal velocity…