## *WHAT makes Earth ROTATE*?

 Quote by D H That website is not only silly, it is wrong. Following their instructions won't change the Earth's rotation rate one bit. There will be a slight change (very slight!) in the Earth's rotation rate when the car accelerates. The car will not change the rotation rate one bit while the car is driving at a constant velocity. Eventually the car comes to a stop. This also changes the Earth's rotation rate, and the change is exactly opposed to the initial change. End result: zero change.
At first I was going to question your conclusion that the stopping of the vehicle would provide an accelerative force. I had to re-read to see that they are, indeed, using the brakes to stop. It seemed to me the idea had some merit if they allowed the vehicle to roll to a stop by friction.

But no, it doesn't matter. Friction is still a force opposing the rotation. To be otherwise would mean you could grab a merry-go-round and come up to speed without the merry-go-round slowing down.
 Mentor People could change the Earth's rotation rate by driving a lot of cars to the tops of mountains and leaving them there. This would change the Earth's rotation rate for the exact same reason that the Java earthquake changed the Earth's rotation rate. To conserve angular momentum, the rotation rate must decrease if the inertia tensor is increased.

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 Quote by D H People could change the Earth's rotation rate by driving a lot of cars to the tops of mountains and leaving them there. This would change the Earth's rotation rate for the exact same reason that the Java earthquake changed the Earth's rotation rate. To conserve angular momentum, the rotation rate must decrease if the inertia tensor is increased.
I think a more practical way to do it would be to pump the earths mantle up a space elevator and let it solidify into a dyson ring. hmmmmm.... might increase the plate tectonic activity for a while. could be deadly to all life on earth. hmmm...... Why do we want to change the earth's rotation?
 Recognitions: Gold Member Here's some good information, helps me a little. Tiny changes can produce drastic results, we need special instruments to measure some changes. Now for something very visual, watch the rear wheels of a dragster when the starting light turns green, spin rate really makes a difference. If climate change is caused by a slowing of earth's rotational speed, my question would be, (can), and how much rocket force, would produce an increase of any magnitude, if they were placed at proper angles and spaced around the globe at maximum elevations, and fired at the same time. I can't do the math (yet) but i do believe that thoughts like this can lead to some thoughts that might prove worthwhile. http://www.nasa.gov/home/hqnews/2005...arthquake.html

 Quote by OmCheeto I think a more practical way to do it would be to pump the earths mantle up a space elevator and let it solidify into a dyson ring.
This would be a tad moe difficult for citizen participation.

 Why do we want to change the earth's rotation?
Because it's a cheap and fun way to spend a Sunday afternoon!