• @L3mmyW1nks
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    1326 days ago

    See figure 3 here: https://en.m.wikipedia.org/wiki/Thermodynamic_temperature

    As mentioned above, there are other ways molecules can jiggle besides the three translational degrees of freedom that imbue substances with their kinetic temperature. As can be seen in the animation at right, molecules are complex objects; they are a population of atoms and thermal agitation can strain their internal chemical bonds in three different ways: via rotation, bond length, and bond angle movements; these are all types of internal degrees of freedom.

    tl;dr Water be jiggly. Amount of jiggle is hard to put a number on

    • @davidgro
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      326 days ago

      It would still be possible to answer the speed question, you just get different answers for different substances (and even phases of the same substance) at the same temperature.

      Since something like water does have those additional ways to store energy, my guess is it would be slower at room temp than another liquid with less complex molecules that have about the same mass each. (If there is such a thing)

      Also I expect different answers for each of mean, median, and mode speeds.

    • @Zachariah
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      326 days ago

      So if I were jiggling, I think I could come up with a speed. I’d figure out how far I’m moving, and how long it takes me to move. So I could measure from far left to far right of the jiggle (let’s say 18in.) and then how far to go from far left to far right and return to the original position. If that’s 2 seconds, then that’s 1½ feet per 2 seconds which can be converted to any other speed such as km/hr.

      • @dohpaz42
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        326 days ago

        let’s say 18in.

        Show off. 😠

      • @ninja
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        226 days ago

        The jiggly argument is about not all parts moving at once or in one direction. If you jiggled to the right by taking one 18 inch step to the right, sticking your left arm straight left, waiving your right arm in a complete circle, holding your left foot 3 inches off the ground, and squatting down 10 inches how far have “you” moved?

        • @Zachariah
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          126 days ago

          How does the thermometer get its answer? I’d measure that part.

          • @FooBarrington
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            226 days ago

            The answer by the thermometer is the temperature, which is based on more degrees of freedom. You’ll have to define some mapping between the other degrees and velocity.