I was watching an XKCD “What-If” video recently and Randal off-handedly mentions the title fact as a given. Upon a further Google search I see explanations about why sound moves faster in liquids than gasses but nothing for my specific question. Is there an intuitive explanation for that fact or is it just one of those weird observable facts with no clear explanation

  • UnderpantsWeevil@lemmy.worldEnglish
    2·
    2 days ago

    Might help to look up the definition of Terminal Velocity.

    Terminal velocity is the maximum speed an object can reach while falling through a fluid (like air or water). It occurs when the force of gravity pulling the object down is balanced by the fluid’s resistance, or drag, pushing it up.

    As the speed of an object increases, so does the drag force acting on it, which also depends on the substance it is passing through (for example air or water). At some speed, the drag or force of resistance will be equal to the gravitational pull on the object. At this point the object stops accelerating and continues falling at a constant speed called the terminal velocity (also called settling velocity).

  • marcos@lemmy.world
    8·
    3 days ago

    Just to add because nobody mentioned that yet… But you can always push stuff faster than the speed of sound, it will just stop being a liquid, and probably explode, but there’s no law saying the material can’t go faster.

    • UnderpantsWeevil@lemmy.worldEnglish
      2·
      2 days ago

      But you can always push stuff faster than the speed of sound

      Sure, but said stuff can push back at you in turn, on account of Newton’s 2nd Law. At some point, you reach an equilibrium between the force applied to the material and the reflected force due to resistance.

  • sem@lemmy.blahaj.zone
    2·
    3 days ago

    Does this mean that a drop of water can’t move through air faster than the speed of sound in air?

    Or that a drop of water can’t move faster than the speed of sound in water anywhere?

  • octoshrimpy@sh.itjust.works
    2·
    3 days ago

    Imagine the liquid as a road, and the sound travelling through it as a runner on said road. Now, sound is faster than the road, because road isn’t moving anywhere. But if we replace the road with one of those airport speedwalking walking pads (kinda like escalators but flat on ground), now the ground is moving, but as luck would have it, the runner is now moving even faster. The more you speed up the pad, the faster the runner moves, even if the runner themselves has not increased their speed.

    Weird stuff, but it does make sense. :)

  • ℕ𝕖𝕞𝕠@slrpnk.net
    2·
    3 days ago

    So, sound is vibration, right? And it’s going to vibrate as fast as it can, at the fastest rate that liquid can move. So it’s not that the rate of movement comes from the speed of sound; if anything, it’s the reverse.