I think Shakes is saying there would be a reduction in volume, not mass and with the Earth’s creamy nougat center…think about reducing the volume of a Snickers bar.
I don’t know if he’s right or wrong, but that’s what he’s saying.
Yes, thank you. I articulated it poorly in my earlier post.
What if the entire universe except the Earth disappeared? Would we still be spinning? How could we tell?
Yes, we would still be spinning and we could tell by the Coriolis effect.
Any other way?
And if we stopped spinning in such a dark universe, would the coriolis effect stop?
I’m assuming that we need big storms to see it, as the coriolis effect supposedly is too weak to actually affect bathtubs and sinks.
Centrifugal force?
But I guess you wouldn’t notice it unless the earth stopped spinning abruptly.
I’m not at all sure it’s rigid enough to avoid immediate collapse however. This has come up before in discussions about hypothetical oddly shaped planets, and on a planetary scale rock or any other real world material has effectively no structural strength; the forces involved are too large.
Yes, Coriolis arises only as an artefact of the planet’s rotation. Without it, air masses would flow North and South, not northeast/southwest. I imagine circular storms would still have to spin one way or the other, just as bathtubs and sinks do (they are far too small to be meaningfully affected by either the Coriolis force or the tide).
The change in force due to no rotation would be very much larger than that due to the loss of a thousand feet of ice. So at least the initial change in shape would be much more rapid.
That is a matter of debate. If Mach’s Principle is true, then which frames are inertial or not is determined by the overall distribution of matter in the universe. If everything but the Earth disappeared, then the overall distribution of matter in the universe would just be “the Earth”, the metric tensor would adjust so that the Earth is non-rotating, and you wouldn’t feel any Coriolis effect.
Assuming that Mach’s principle is incorrect, though, you could also tell by a Focault pendulum, such as are found in nearly every science museum in the country.
Question eburacum45. How is the northern hemisphere “recovering”? I’ve never heard of this.
I believe what he’s referring to is the land surface rising, due to not being weighed down by an enormous blanket of ice - right?
Of course, “enormous” is a relative term when compared to the mass of the globe, but pretty enormous in human terms.
That’s right. Note the illustration that shows how the material in the mantle has moved from surrounding regions into the rebounding area;
if the Earth were to stop spinning, this would happen on a massive scale, as the equator falls and the rest of the world rises.
Thank you.
Ashes where the bodies burning
No more war pigs have the power
Hand of God has struck the hour