If the earth stopped spinning would we fall off of it? Which way would we fall if we did? Or would there just be less gravity?
Grant Shepard, age seven, Oak Park, Illinois
You gotta be prepared for anything, kid. If you’d asked this a couple years ago I would have said, “The earth stop spinning? Right, and Bill Clinton’s gonna be reelected president.”
If the earth stopped spinning we would not fall off of it. Despite what a lot of people apparently think, spinning has nothing to do with gravity, which is a function of the earth’s mass.
On the contrary, spinning tends to throw you off the earth. Were the earth to stop spinning, we would be stuck here more firmly than ever. That’s because, due to the lack of centrifugal force, you would weigh more.
(And please, don’t tell me there’s no such thing as centrifugal force. I know that. I just don’t feel like going into a long explanation.)
How much more would you weigh? Well, figuring in your newtons, your velocity, and your gravitational constant … about five ounces for a hundred-pound person.
At the equator.
An effect you could achieve right now if you merely walked to the north pole.
And which might be canceled out anyway because a stationary earth would cease to flatten at the poles. So maybe not that big a deal.
The real difference, apart from the end of life as we know it, would be that, no matter what hemisphere you were in, the bathwater would go straight down the drain.
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