Can we stop the earth's rotation?

[Jimbot]

tru dat

 

[AlphaWolf]

because it's the moon which keeps the earth going around. You need to destroy the moon to stop the earth.

What? Where the hell did you get this from?

 

[thine_impalor]

The formula F=Gm1m2/r^2 is the only formula I know that could calulate the force required, but I'm only an amateur physicist, so its probably more involved with even more factors to take into consideration. Gravity is the weakest of the fundemental forces, but acts over an infinite range, so any number of bodies in space can be affecting the Earth's rotation.

According to the actual law of gravitation EVERY body in the universe attracts every other body in the universe with a force = Gm1m2/r^2. we had a phy question last yr, would movements of one's fingers disturb the stars?? according to the answer it WOULD disturb the gravitational force between the star and the person..sounds kinda far fetched but supposedly true...

I agree to stop the spin of the Earth, you need a force that equals the gravitational forces that keep it spinning. People walking is nowhere near going to do this, but an asteroid impact could also alter the Earth's rotation.

I agree with u here partially, thats what probably happened to uranus...it rotates in a diff manner PROBABLY caused by some sort of cataclysmic collision with something..that something is DEFNIETLY bigger than an asteroid tho bcuz uranus is much bigger than the earth...oh yeah and i don't think asteroids will be enough to alter the earth's rotation tho bcuz asteroids have impacted the earth many times...remember asteroids are not particularly large, well they r but they r miniscule in celestial terms..(say 1-2km wide) but maybe a comet?(come to think of it i have no idea how large a comet is but much larger than asteroids i guess)

 

[hotquik]

I think you are missing my point here... what i sayd before is that our small mass (compared to earth's mass) could be compensated while a very, very, very, very long application of our force.
Is this wrong?

 

[thine_impalor]

I think you are missing my point here... what i sayd before is that our small mass (compared to earth's mass) could be compensated while a very, very, very, very long application of our force.

I should think it is wrong actually because no matter how long we apply the force at every turn the earth would be able to resist the force the ppl exert....

 

[Jimbot]

no, hotquiks right. I dont remeber the equation, but if our small mass produced a small force for a <b>very</b> long time, then it would have an effect.


And the moon really doesn't have to do that much with the turn of the earth. The only thing the moon moves is the tides, because the water is flexible.

 

[Eagle]

Think of it this way guys, say your on a bus. Every one crams tot the front of the bus. Then everyone walks to the back of the bus. Would that stop the bus? No. The force exerted on the bus by its internal combustion engine is greater than that of the force of the people in it walking to the back of the bus.

Thus is true for the earth as well. The population of the earth is insignificant when compared to the magnitude of gravity that the sun and moon exert on the earth making it imposible for them to affect the earths rotation.

Add to that every car, every train, every land vehicle moving int the same direction at top speeds and you still would not have enough force to make a difference. Its really quite amazing how small we really are.

 

[AlphaWolf]

The sun and the moon don't cause the earth to spin, thats momentum. (which actualy happens to be slowing down, hence days are slowly getting longer anyways)

 

[ShadowPrince]

I think you are missing my point here... what i sayd before is that our small mass (compared to earth's mass) could be compensated while a very, very, very, very long application of our force.
Is this wrong?

It's partially true, the main point is not about force or the time this force works on Earth . Until you're inside the system , you can't affect it's speed .
BUT , in your case whats important, it's law of conservation of momentum . It says that the total momentum of a object with no outside force remains constant regardless of changes within the system . So , answering to your question , when you walk , you're *affecting* the rotation of earth and even axis of rotation .
But,when you stop your movement , rotation and axis back to normal .
The very simplified formula for someone, who wants to stop earth rotation (I used simplified formulas for linear movement,rather than angular movement ) :

M1 * V1 - M2 * V2 = 0

Where
M1 - Earth mass (known)
V1 - Earth rotation speed (known)

M2 - Mass of all people + vehicles + ... combaned in one point (known)
V2 - Their average speed needed (?)

Just put values of (known) things and you can get average needed speed .

So,bottom line, when you moving your finger in some direction,you're affecting Earth rotation,and it's possible to slow it down considerably (several extra seconds per year seems to be reachable) , if we get really orginized ,dont underestimate power of mankind .Btw,destroying the moon will really help ,but i not sure if it will slow down rotation,or speed it up . The good thing is that effect will be permanent , bad - it's probably will be our end .

 

[thine_impalor]

no, hotquiks right. I dont remeber the equation, but if our small mass produced a small force for a very long time, then it would have an effect.

ONLY if the small force is not resisted can it have an effect, in this case, each time ppl walk(in sync) they r pushing at the earth being resisted each time, so it doesn't make any difference....

Basically what Eagle says is right. Even if the total organic mass of the whole earth were used it would still be useless as they would be trivial compared to the earth's mass...