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Joined 1 year ago
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Cake day: July 21st, 2023

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  • I would drive 140km/h regularly, but that seems to be on the lower end in Germany?

    I would say most people go 120-140.

    There are some who go only 100. Some go 160 or 180. Very few go even faster.

    Funny thing: Teslas are on the lower end. You can hardly see them going above 120, and even less when it’s just a little bit uphill.

    Yes, the highways are mostly straight enough, and the white lines are visible etc. Where there are dangerous sections, there are speed limits accordingly.

    But you also have to look carefully: if you go much faster than 130 and the road isn’t good enough for whatever “much faster” is, then you are liable for the outcome.










  • Actually, the answer is complicated.

    Gravity isn’t the only relevant aspect here. Gravity makes that you have to look at the combination of “sun + planet”. They behave like 1 body together. But “sun + 10 planets” is like 10 different of these combined bodies: “sun + planet 1”, “sun + planet 2”, “sun + planet 3”…

    Imagine it was different. Imagine a system of several planets rotating around the sun with all their rotational planes at different angles.

    This system would be very asymmetric all the time. Now in general when asymmetric bodies rotate, then that motion is not stable. They tend to change their motion, that is, the rotational axis changes until it reaches the maximal inertia moment.

    Take a plate or a stick and throw it up high while rotating it at a random angle. Then do it again with a very asymmetric thing. Watch how it’s motion changes.

    It becomes stable when the inertia moment is maximal.

    https://en.m.wikipedia.org/wiki/Moment_of_inertia

    For the system with several planets, the stability of the whole system is maximized when all the rotational planes are the same, because then the inertia moment of the whole system is maximal.