I thought of something today, since we now know in science that when something spins in space, it creates its own gravitational force.
Now, we also know all the worlds spinning action determines THEIR gravity.
So what if the Earth stopped spinning? Would everything just float around?? Imagine rocks, trees, animals, WATER!(ah!) floating around the atmosphere! WOOOAAAHHHH

Just need someone to confirm this theory.

I guess we would all be swept up in to the atmosphere along with everything else , if it was a sudden stop the atmosphere would still be in motion and going so fast we would literally be blown away LOL

thats depressing really

i think we would still have gravity though but i'm no expert LOL .

The Earth's gravity has nothing to do with spinning.

Any object exerts a gravitational pull which attracts other objects. However for it to be noticeable, the object must be really big, like a planet for example.

If the Earth stopped spinning their would still be gravity.

but not as much as there is when we are spinning.

Earths gravity is caused by it's mass, not it's spin... the only thing that would happen if the Earth stopped spinning is one side would fry, and the other side would freeze... IMO

What would happen in the middle?

I think the gravity would be 'greater' without the spin... centrifugal force (the spin), actually tries to throw objects off the surface... IMO

I'm pretty sure that the spinning has something to do with keeping us from being sucked into the sun. It's been 5 years since Astronomy class, and I can't remember!

I think and correct me if i'm wrong but doesn't the earths spinning reduce the gravitational pull slightly by something like 0.3%.

Spot on. Gravity is just the expression of the attraction of two objects in (close) contact. Increased attraction between two objects (in this case called gravity) is directly proportional to the mass of the objects and is inversely proportional to the distance between the objects. A massive object like earth has a certain attraction, or gravity, while the moon, with less mass, has less gravity. I am pretty sure the moon doesn't spin/rotate (relative to earth) yet it still has gravity. Although we don't know for sure as we have never really landed there...

lol, no, the earth no matter what would still create a bend in space-time, hence gravity.

I think you may have been absent that day.

Gravity has to do with the mass of the planet which will be here spin or not. Now imagine being on a merry-go-gound(substitute any spinning ride of choice) that is spinning fast; which way does your body want you to fall? towards the outside of the ride, because of centrifugal force from the spin. At the earths midline we are spinning at nearly 1000 miles per hour, definately no a physicist and ould need waspie to step in, but my guess would be that if the earth stopped that gravity would be in force and if anything the decrease in centrifugal force would slightly add to many peoples weight issues.

we landed on the moon, and if the earth stopped rotating the moon wood still spin around the earth.

If you consider the moon. It doesn't spin at all, but still has gravity. It also has a fair bit less gravity than the Earth due to being a fair bit smaller than the Earth.

Ok, fluffy, that had nothing to do with what I wrote. Yes, the Earth has mass, and so it would still have gravity. I was talking about the spinning and how important it is not just for us to have days.

Anyway, here is a site to answer the OP.
site

What would happen if the Earth stopped spinning?
The probability for such an event is practically zero in the next few billion years. If the Earth stopped spinning suddenly, the atmosphere would still be in motion with the Earth's original 1100 mile per hour rotation speed at the equator. All of the land masses would be scoured clean of anything not attached to bedrock. This means rocks, topsoil, trees, buildings, your pet dog, and so on, would be swept away into the atmosphere.

If the process happened gradually over billions of years, the situation would be very different, and it is this possibility which is the most likely as the constant torquing of the Sun and Moon upon the Earth finally reaches it's conclusion. If the rotation period slowed to 1 rotation every 365 days a condition called 'sun synchronous', every spot in the Earth would have permanent daytime or nighttime all year long. This is similar to the situation on the Moon where for 2 weeks the front-side is illuminated by the Sun, and for 2 weeks the back side is illuminated. This situation for the Earth is not the condition of 'stopped' rotation, but it is as close as the laws of physics will let the Earth get.



If it stopped spinning completely...not even once every 365 days, you would get 1/2 year daylight and 1/2 year nightime. During daytime for 6 months, the surface temperature would depend on your latitude, being far hotter that it is now at the equator than at the poles where the light rays are more slanted and heating efficiency is lower. This long-term temperature gradient would alter the atmospheric wind circulation pattern so that the air would move from the equator to the poles rather than in wind systems parallel to the equator like they are now. The yearly change in the Sun's position in the sky would now be just its seasonal motion up and down the sky towards the south due to the orbit of the Earth and its axial tilt. As you moved along constant lines of Earth latitude, you would see the elevation of the Sun increase or decrease in the sky just as we now see the elevation of the Sun change from a single point on the Earth due to the Earth's daily rotation.

For example, if you were at a latitude of +24 degrees North in the Summer and at a longitude where the Sun was exactly overhead, it would slide gradually to the horizon as Fall approached, but since the Sun has moved 90 degrees in its orbit, it would now be due west. Then as we approach Winter, you would now be located on the dark side of the Earth, and would have to travel in longitude to a location 180 degrees around the Earth to see the Sun 1/2 way up the sky because in the Winter, the Sun is 48 degrees south of its summer location in the sky. It's a little confusing, but if you use a globe of the Earth and orient it the right way, you can see how all this works out.

As for other effects, presumably the magnetic field of the Earth is generated by a dynamo effect that involves its rotation. If the Earth stopped rotating, it's magnetic field would no longer be regenerated and it would decay away to some low, residual value due to the very small component which is 'fossilized' in its iron-rich rocks. There would be no more 'northern lights' and the Van Allen radiation belts would probably vanish, as would our protection from cosmic rays and other high-energy particles. This is a significant biohazard.

The Moon rotates at the same speed as it orbits the Earth, 27.32 days... the Moon spins about its axis one full revolution so we always see the same face of the Moon...

Ah. But he said relative to the Earth. From the Earth's point of view, it doesn't seem to rotate at all. But I'm just being pedantic now.

Wow, we talked about this in my geophysics class. *pulls out notebook*

1) One side would be in complete darkness for 6 months and the other in complete light. 6 months later, the reverse happens. And the temperatures would be way more extreme than they are now.

2) The atmosphere would still be moving at 1700 km/h which would suck things that are not weighed down from earth.

3) You would weigh a bit more (a pound more)

4) No magnetic shield to fend off harmful radiation

I think FluffyBunny's post was quite relevant to what you wrote because he discussed centrifugal force, which is what keeps the earth from being "sucked into the sun". I'm pretty certain the path the earth takes around the sun does not have anything to do with how fast the planet spins. And I think that your link did not answer the OP as it did not discuss gravity. Just felt I needed to point those things out.

I think FluffyBunny touched on this too. Does this mean that a person would weigh more at either of the poles than at the equator? I remember reading that the earth is not a perfect sphere, it is slightly "squashed" at the poles. Does this mean that at the poles a person would be closer to the core of the earth, therefore subjected to a stronger gravitational pull? I think it would. Sorry if this seems like nitpicking.

The spinning is two ways, around itself, (why we have the equator) and then also around the sun. It as nothing to do with gravity, I agree wthat it will be slightly less gravity if anything, cenrtifugal if it "stopped". However, the earth is really not spinning at alll really, it's "flying" in a straight line as the universe is expanding. If it stopped spinning something has happened or the universe stopped. You can't say that you wll fall into the sun and stuff, it will be "worse" or weirder than that, since it would have to do with 4D space, a black hole perhaps.

Yes because of centrifugal force.


Yes the other side which is permanently dark would freeze but the other side that is exposed to sun every time of the year it would not fry but would be in a continuous storm surge, like a permanent typhoon or hurricane.

You are only half right. The earth is spinning. When the earth formed, the gases cooled down and the earth began to spin faster. Conservation of angular momentum means that the earth needs to stay spinning at a constant rate unless the moment of inertia changes (it doesn't, or rather the change is so small that it can be neglected). Also, Newton's law states that an object in motion will continue to stay in motion unless acted upon by another force. Since there is no other force acting to earth, it continues to rotate (again, the force by the moon is so small it can be neglected). So you are right in assuming that something has happened but that does not necessarily mean that the universe has stopped.

No but what would happen is the dark side of the world would likely get cold leaving it a baron waste land. the other side would mostly be habitable and the main ocean body a super massive hurricane would spin endlessly.

Ok, but the hurricane would eventually reac the other side, cooling it down, so it would balance out and there would be just the normal weather.... right?

It would not be normal weather. The side without light would experience very cold temperatures, far extreme than what we have today. Similarly, the side with light will be hotter than normal. There would not be a hurricane. Assuming the earth just stops spinning (without slowing down first), the powerful winds would be caused by the atmosphere, which would still be traveling at 1700 km/h.

The moon does spin, it's in sync with the Earth so we always see one face. It rotates on its axis one full time for each revolution it completes around the Earth.



It had everything to do with what you wrote, the centrifugal force is the result of the Earth rotating.



If the Earth were a perfect sphere, then yeah, you would weigh less more at the poles of the Earth. If you were closer to the core the gravitational force exerted on you would be less, in fact if you were at a hollow chamber in the center of the Earth you would float because there would be no gravitational force at all (the Earth's mass would be equally distributed in all directions, cancelling itself out).

if the world stopped turning

it would be game over for

5 billion humans and would

be few habitable place left

Sorry I have to disagree. I feel that the effects of gravity would be higher at the poles because you are not being affected by centrifugal force as much as at the equator. Centrifugal force acts in a direction away from the centre of the spinning object. Think of a bike tyre with mud on it. The faster it spins, the more chance the mud will fly off the tyre. This is centrifugal force acting away from the centre of the tyre.

I also think that the effects of gravity would be more the closer you go to the centre of the earth. Gravitational force is inversely proportional to the distance you are from the object. What that means is that the further away you are the less gravity there is, while the closer you are the more gravity there is. A meteorite flying by the earth might have its course deviate a little toward the earth because of the earth's gravity, but it may not enter our atmosphere and may continue on its way. However, the closer the meteorite is, the more chance there is that it will be drawn towards the planet because earth's gravity is stronger.

Not without Earth's gravity !

sama

I'm pretty sure that centrifugal force has nothing to do with the Earth orbiting the sun.

The Earth is attracted to the sun, however it is also moving beside it (ever since it was created). So it keeps being attracted to the sun but shooting past the sun due to it's sideways movement. It's sideways movement doesn't stop, because there's no friction in space to slow movement down. Something that moves in space, keeps moving until something else stops it.

Well that's how I see a planet's orbit to work anyway. I'm sure someone will correct me on the details (or at the very least, explain it more clearly than I can).

My bad, I meant to say you would weigh more at the poles. Stupid slip up.



I know about the inverse square law, but you're looking at it too simplistically. Look at this image I drew:



The ball on the left is at the surface, and so has the entire mass of the Earth acting on it. The one on the right has dug down nearer to the core, which means there is now some mass above it which is trying to pull it upwards, this cancels out the effect of the mass on the other side which is trying to pull it down. Now effectively there is only one smaller sphere of mass which is acting on it. If you're at the center of the Earth, all of the mass will be cancelled out, and you'll float.

Oh boy, Let's clear a few things up.

If the earth were to suddenly stop rotating, your weight on earth would slightly increase. The centripetal force created by our rotation about our axis serves to slightly reduce gravity. We can calculate this where it would be the strongest.

We know the acceleration due to gravity is 9.81 m/s² and we know we can describe centripetal acceleration with v²/r, where v is the velocity and r is the radius of the object.

The radius of earth's poles are 6,356 Km and a day has 86,400 seconds. So we can find v by,

6356 km (1000 m/ 1 km) = 6,356,000 m
The circumference would then equal (2Pir)= 6356000*2*pi =39,935,925 m

So to calculate velocity (V=D/t) = 39,935,925 m/ 86,400 s= approximately 462 m/s for the velocity of earth's poles.

Now using our equation for centripetal acceleration,

(462 m/s)²/ 6,356,000 m = .03361 m/s².


Now this acceleration acts in the opposite direction of the acceleration due to gravity, so to calculate the reduction
9.81-.03361 =9.78 m/s²

a difference of only .3%.

So if you weight 200 lbs now, you would weigh 200.6 lbs if earth stopped spinning.



Rotation can be used to create artificial gravity. For instance, if you were on a space ship spinning very quickly, the centripetal force would pull you away from the ship. If you were to order your floors and walls (floors would really be on the outside) then this could serve as a fake gravity. Like a roller coaster, the CF keeps you in your seat on the loop, if you put a floor on the 'upside' down part of the track, in space you could walk around on that piece of track like you could the ground on a planet.

s'cool


Oooooh, I get it now. That explains things very plainly. I see what you mean. Yep, I agree. Thanks for that. Sorry it took so long for me to understand.

gravity would still obviously exsist with out the earth spinning the act of spining make us reduce our gravity, the earth is spining over 500mph could you imagine the amount of force exserted on you if it stoped ok it you want to find out i you jump out of a jet traveling at 500 miles per hour and see if the wind makes you want to stay in one spot and not fall.lol the act of gravity has to due with mass, quantum mechanics and the law of attrations not the cool little spinny thing in the carnival that makes you stik to the wall, that is cintrifical foces keeping you at the wall not gravity. gravity is caused by atoms being attracted to one another the more atoms the more gravitational force atoms are attracted to one another due to the law of attarction protons of one atom are attracted to the electron of another visa versa theywill not conect due to this attractioin because there are minor forces of repulsion from proton to proton and electron to electron, so most STABLE atoms won't attatch to one another but the ones that have an unstable electron cloud will jion wilth another unstable atom to reach a point of stability. its simple chemistry and quantum mechanics its easy to understand. if the earth were to stop rotating life on earth would be in grave danger the day side being to hott and night being to cold there might be a boundary of a few miles where life could survive on the surface or life might exsist in hydro thermal vents on the night side but human life as we know it could not survive a planet like that if were were to live like we do now.

if you could in theory stop the earth all at once everything would be flong aways and then come crashing back to earth

Most of the physics in this thread is appalling and beyond redemption.

Part of the problem might be that terms haven't been defined and no
explanation is given for what force stopped the rotation. There is a force
which is stopping rotation now and the days have been getting longer
because of it. It is caused primarily by the tidal effects of the moon.

Earth's rotation has relatively very little import on its planetary motion
or the motion of bodies around it. It is, of course, critical to the even
distribution of solar heating and what time the sun rises.

Did somebody call for a substitute instructor?

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.

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.

I thought I put that in my post above, but reading over it again I guess I forgot. Cladking is correct though, our rotation about our axis is of no import to our rotation about the sun.

You have the right idea but the direction water would spin down the drains
would be random rather than predisposed to one or another.

You're right that weight change would vary dependent on the position rel-
tive to where the equator had been.

I think that is the real issue here, don't you?

So basically from what I read so far, for there to be no gravity on the Earth, the mass would have to cancel out or not exist - which is impossible, obviously... everything has mass. So the mass causes the rotation of the earth, but NOT vice versa. Say if you stopped the spin of the earth, it would not affect the mass, correct? Thats how I take it anyway.

So Raptor X, what you are saying is that if we dug half way to the core of the earth, we would weigh significantly less. So really, there could be Subterranian civilizations utilizing this right now.... just a crazy thought. We could do this!
Alright guys, hop on the bus, we're goin to hell!

Yeh, that's where Hitler's Nazis, in conjunction with the underground lizard-men, perform experiments into the field of anti-gravity vehicles. But that's a topic for another forum...

A body in motion remains in motion unless acted upon by an outside force. This is inertia.

You can think of inertia as a property of matter (which has mass) though this isn't really the
best science probably. The Earth rotates because of its rotational inertia; there is no out-
side force to stop it in a brief time frame. Inertia is mass times speed. It's a vector equa-
tion and is relative to defined objects.

Mass has inertia whether it's moving or not. You can't even really define not moving since
the entire universe might be moving for all we know. The planet has many liquid charact-
eristics so the means employed to stop such a large sloppy mass would be important to de-
scribing the effects. But simply changing an object's inertia has little effect on its mass ex-
cept at relativistic (very high) speeds.

Escape velocity of the Earth is 5.5 miles per second and the spin is about .3 miles per sec-
ond (at the equator) so nothing should be thrown clear.

So if the world stopped turning the safest place would be at the North and South poles?

rotating has nothing to do it with its gravity, just its outward force, look at mercury and glise 581c they do not rotate, yet they have gravity.

Assuming that the world just suddenly stopped, then you wouldn't be safe anywhere except maybe in a deep cave. That is because the atmosphere would suck you up.

if suddenly the earth stopped moving, we well the earth`s magnetic field would stop in a few years, the molten metal would stop spinning. And one side would be icy and the other side hot, with a thin belt of moderate climate.

A cave might not be the best place to be when a few thousand
cubic miles of sea water came back down. Of course, after you
hit the cave wall at 1000 MPH it shouldn't matter.

We still haven't specified the mechanism for stopping the rotation
so perhaps the Earth's crust including the cave will take off at a
high rate of speed as well.