• Idreamofcheesy@lemmy.world
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      23 days ago

      Not quite. When you’re rotating, you are constantly accelerating in a tangent direction to the diameter. So the poster is right that we should be feeling a force shooting us away from the center of earth.

      Except the force of gravity cancels out the centripetal force and then some.

      So [force of gravity] - [centripetal force of Earth’s rotation] = 9.8m/s^2

      • cynar@lemmy.world
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        23 days ago

        The difference is about 0.5%. A mass weighing 100kg at the north pole would only weigh 99.5kg at the equator. Most of the difference is the centerfugal force of the earth’s rotation.

        I’ve not checked the numbers, but apparently it’s detectable in Olympic sports. More height records get broken at equatorial latitudes that higher ones.

        • wanderer@lemmy.world
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          22 days ago

          A mass weighing 100kg at the north pole would only weigh 99.5kg at the equator

          That assumes a perfectly spherical earth. The earth is not perfectly spherical.

        • tweeks@feddit.nl
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          23 days ago

          Interesting, would the muscles of someone living far away from the equator be stronger in general than compared to someone with the same genes / lifestyle on the equator?

          • cynar@lemmy.world
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            23 days ago

            0.5% is so tiny that it disappears into the noise. It’s a 1 in 200 difference. In theory, it would make a difference. In practice, you won’t be able to measure it. Other confounding factors would bury it.

        • Idreamofcheesy@lemmy.world
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          23 days ago

          It sounded like the guy meant the 1700km/h is a velocity, not an acceleration, which is why we don’t feel the force of acceleration.

          I was pointing out that spinning is acceleration, just in this case we can’t feel it due to other forces.

      • db2@lemmy.world
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        23 days ago

        What are those pre-math numbers though? How screwed would we be if rotation doubled or stopped (regardless of the virtual impossibility)?

        • Idreamofcheesy@lemmy.world
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          23 days ago

          Have you seen the elementary school experiment where you spin an egg on a flat surface, then you stop the egg and let it go and the then the egg starts spinning again?

          If the earth suddenly stopped spinning, the atmosphere would still be spinning at 1700km/h.

          A cat 5 hurricane has wind speeds of 253km/h. So we’d be boned.

      • kerrigan778@lemmy.world
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        22 days ago

        Only on the equator, the force is just tiny, it produces major weather systems through the coriolis effect but only on giant scales. This would be like saying people get dizzy if they stand near the pole.