If the earth were to suddenly start rotating faster, would it have any effect on our weight and, if yes, what?

anela19

Yes, we would weigh less. Oct 01 05, 3:10 PM

Arpeggionist

Only our apparent weight would be slightly diminished. This explains why creatures as large and cumbersome as the saurpodian dinosaurs managed to move around and survive in an era when the rotation of the earth was much faster (and its orbit was slightly shorter as well). But it would have to be a lot faster to really affect objects in a very significant way. I think the speed of the rotation of the planet has more of an effect on wind and water currents than on living beings. (Jupiter's Big Red Spot is stronger than anything which could happen on Earth, and its rotation is extremely fast.) Oct 01 05, 4:18 PM

gmackematix

It's an interesting idea, Arpy. Do you have a site that claims the difference between the Earth's rotational speed now and 65 million years ago is enough to have made the mobility of dinosaurs significantly more than it would be today? Our actual weight is the gravitational force acting on us, which is dependent on our distance from the Earth's centre of mass and the relative masses of us and the Earth, neither of which would change with the Earth's rotational speed. So our actual weight would remain the same. Our apparent weight also depends on the centrepetal force on us by virtue of the Earth's rotation. This force pushes up on us away from the Earth's centre of rotation proportional to our mass and the square of rotational speed and is inversely proportional to our distance from the centre of rotation. As the rotational speed is small (one rev per 24 hrs) and the distance is great, then this force is tiny. Even if the Rarth span twice as fast, the centripetal force would not be much greater but our apparent weight would be ever so slightly less. Oct 02 05, 5:49 PM

gmackematix

Sorry, my mind wanders back to planet Rarth on occasion, but the same applies to Earth. Oct 02 05, 5:53 PM

gmackematix

And do you think if I keep my head down, nobody will notice my confusion between speed and angular speed in my argument? Oct 02 05, 5:56 PM

peasypod

Nothing goes unnoticed around here gmack, but being the polite gal I am....And of course there's that Brief Moment in Time when you were Whistling Dixie on the Planet Rarth, that may have something to do with it... Oct 02 05, 6:58 PM