Mastodawn

makeshiftreaper Jul 20, 2025

Why can't a liquid move faster than the speed of sound in that medium?

Why can't a liquid move faster than the speed of sound in that medium? - Lemmy.World

I was watching an XKCD “What-If” [https://youtu.be/pfbzrrcQZjs] 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

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marcos Jul 20, 2025

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.

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UnderpantsWeevil

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

Sure, but said stuff can push back at you in turn. At some point, you reach an equilibrium between the force applied to the material and the reflected force due to resistance.