*WHAT makes Earth ROTATE*?

DaveC426913

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.

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.

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. 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?

RonL

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

DaveC426913

This would be a tad moe difficult for citizen participation.

Which also answers your other question:

Because it's a cheap and fun way to spend a Sunday afternoon!