What would happen if the Earth suddenly stopped spinning? I know its unlikely, but just humor me.?

Answer 1

Raymond's answer is correct and we should vote for him when the time comes, those who care about accuracy.

Nonetheless there are two points that he needs to work out better. Maybe if he sees my own reply he can re-work some of this before the option to edit is closed off.

First, he mentions but underplays the release of heat that would be caused by the loss of momentum. The reasoning about what water would do is clever in Raymond's answer, but basically the release of heat energy would probably vaporize any water and all living things so the flow effects would be negated by the vaporization. Kinetic energy always dissipates into heat. This is true of your car brakes and also when you slam your fist on to your desk. It's just a question of being able to measure that heat. If you take a hammer and start pounding metal, the metal and the hammer will get hot. If you stop the Earth that energy will go somewhere, unless we're just talking magic.

The question came up during the famous Scopes Monkey trial in Tennessee in 1925. Clarence Darrow noted that if the "sun stood still in its tracks" as the Bible says happened during the battle of Jericho, that the Earth would melt. But of course, if a divine being were to stop the rotation maybe he would also stop the laws of thermodynamics. This seems very complicated and if I were a divine being I would just clear the battlefield of the opponents. Strike them with lightning or something. Less trouble. But it would be even simpler to note that all great soldiers feel that, in the heat of battle, it seems as if time stands still. This subjective feeing is basic to the way our brains work under fight-or-flight stimulus.

Now, the OTHER point to be made is that at some point the Earth will become tidally locked with the moon and in fact stop rotating (as we know it) or more accurately have a rotation equal to one solar year. So the question about the Earth stopping is not a hypothetical. The process of stopping is going on right now.

This is going to take a long time, though. But days today are much longer than when life evolved.

I would like to point out to everyone that posts on these groups that there are often some very serious issues under a lot of questions that seem ill-informed. We improve the quality of this service by taking people seriously and by being courteous. Answers are always improved by bringing real Physics into the question, too.

Thanks Raymond.

Good luck,
GN

Answer 2

Weird question, but I'll humor you as you asked.

If some force compelled the earth to stop rotating all of a sudden, the angular momentum would have to go somewhere. The energy released might be enough to break apart the planet, and certainly much energy would be dissipated as heat. Objects on the surface of the planet would continue to move with the planet's former rotation, that is, they would suddenly lurch eastward, since they were in motion along with the planet, and they will continue to move until an outside force (friction with the planet's surface or atmosphere) makes them stop.

Somehow, I don't think this was what you're looking for, so let's grant another violation of the laws of physics, just for fun: We'll have the planet stop spinning and dissipate the angular momentum immediately and painlessly. The earth continues to revolve around the sun, and gravity is unaffected.

If the earth's rotation is zero with relative to the entire solar system, then the fixed stars seen from any location on earth never move, none rise and set. The sun creeps slowly across the sky as the earth's revolution around the sun changes its position. The sun rises in the west, and six months later, sets in the east, followed by six months of night. I speculate that this would make life as we know it impossible, and would certainly destroy civilization.

If the earth makes one rotation for every revolution, the effects cancel relative to the sun. The earth would always have the same face presented toward the sun in the same way that the moon now does to the earth. The sun would not move from its position in the sky, and the dark side, in perpetual night, would be able to see the fixed stars rising and setting, moving from east to west but taking a whole year to go all the way around.

Answer 3

Oh, good lord...

Despite all the posters that clearly don't have the slightest clue what they're talking about, rotation has absolutely nothing to do with gravity. Zero. The Earth's gravitational pull will be exactly the same, regardless of whether it is rotating or not.

However, if the Earth slows it's rotation, the angular momentum will have to be transferred somewhere, and the greatest recipient of that transfer will be the moon, which will be thrown outward into a much larger orbit.

And as Igloo Man stated, there will be tidal effects as well. How serious those effects might be would depend upon just how suddenly the rotation stopped.

Once the Earth stopped rotating (and thus would remain tidaly locked with the sun), obviously one side of the Earth would forever be much hotter, while the other would be much colder. But the atmosphere would still distribute enough of the heat to make parts of the Earth habitable, probably in a band a couple of thousand miles wide around the terminus. But the regions in the middle of each of the light and dark hemispheres would likely be unable to support life as we presently know it.

Answer 4

Earth is rotating at a speed of about 1100 miles per hour. If our planet suddenly stopped rotating, the atmosphere would still be in motion at that speed. The atmosphere would be moving so fast it would literally sweep the land masses clear of anything not anchored to bedrock, this would mean rocks, soil, trees, buildings, people and animals. All would be swept up into the atmosphere. If the Earth's rotation slowed down gradually over millions of years, and this is the most likely scenario, it would be a very different story. If the Earth slowed down to one rotation every year, called synchronous rotation, every area on Earth would be in either sunlight or darkness for one year. This would be similar to what the Moon goes through where for two weeks the front side of the Moon is illuminated by the Sun followed by the front side being in darkness for two weeks

Answer 5

If between one second and the next, the Earth's rotation suddenly stopped, the rotational energy imparted to the "loose objects" on the surface (i.e.: You and Me) would continue in the direction they had been travelling in prior to that. Generally speaking, those not inside a properly durable structure, will fly up off the surface, presumably eventually reaching low orbit or more. Those inside said structure, would end-up smeared along the interior western side of it.

The western shorelines around the world would be instantly destroyed as the oceans / waters overflow and erode them.

Assuming the planet became tidelocked, all the water and atmosphere would slowly turn into a massive glacier on the side opposite the sun.
If the planet was not tidelocked, the planet would gradually become uninhabitable as our surface temperatures start climbing to rediculous levels, much the same as the surface temperatures of the moon.

To repeat an statement here:
Rotation has ZERO effect on gravity. Gravity is based on MASS, not rotation. The planet will NOT fall out of orbit...ever...due to a sudden stopping of rotation.

Answer 6

If the Earth suddenly stopped spinning, (which is impossible, really), forward motion would continue for all objects on its surface. At the equator, all objects would, because of inertia, continue to move at 1020 miles an hour. At that speed, everything would burn up in the atmosphere due to friction. All cities would be reduced to rubble or powder. All life on the surface of the Earth would be destroyed. The oceans would probably flood most of the land.

Answer 7

k i have to ask... WHAT DOES GRAVITY HAVE TO DO WITH THE ROTATION OF THE EARTH!!! it looks like one person said it and everyone else just jumped on the band wagon. ok now that i have that out of my system to answer your question what would happen if we stopped spinning.. not much after the initial stop, that would be a disaster but the dark side would not start to freeze right away, if ever because the 24 hour day would be 365days long. and it would cause a lot of storms, witch would circulate the hot and cold air. the earth would change its magnetic Field i don't think it would get rid of it altogether tho.

Answer 8

Ha Ha Ha
(there, you've just been humored)

We would NOT fall into the Sun. What keeps us on orbit is our speed along the orbit (29.786 km/s), not how fast we spin on our axis.

Depending how quickly you stop the spin, then the rate at which things happen will differ:

We would NOT be shot into space. Earth's surface speed is 0.5 km/s at the equator. We'd need almost 8 km/s to achieve lowest orbit and 11.2 km/s to escape Earth's gravity completely.

The Moon will NOT be shot out or made to go into a larger orbit or whatever else (unless, of course, the Moon is actually used in stopping our spin -- which it is actually doing at a very slow rate, and moving out at 4 cm per year in response to the transfer of rotational energy).

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We are carried by the spin. If you stop the spinning too fast, we will be plastered against walls (unless they are ripped from their foundations and get tossed along with us).

Let us assume (just for the fun of it) that the spin is brought to zero in 47.4 seconds. Let us not worry how for now, except that we will consider the cause as being part of Earth (we are not involving the Moon, the Sun, the Galaxy nor the space-time fabric...).

A point at the equator, on Earth's surface, is travelling 40,000 km per sidereal day. That is 40,000 km in 86,164.1 seconds = 464 metres per second.

To go from that rate to zero in 47.4 seconds requires a deceleration of 464/47.4 m/s^2 = 9.8 m/s^2

Earth's gravity would continue to exist, unaffected. It pulls everything towards Earth's centre at a rate equivalent to an acceleration of... 9.8 m/s^2.

Therefore, every object on Earth's surface at the equator would feel, for the 47.4 second duration, a pull of 9.8 m/s^2 towards Earth's centre (i.e., perpendicular to flat, level land), AND a pull of 9.8 m/s^2 towards the East, parallel to flat, level ground. (Level, of course, meaning BBB: Before the Big Braking).

A person standing on flat land BBB, would suddenly feel as if they were on a 45 degree slope (East being downhill) and their weight has suddenly increased by 41.4%. It would be difficult to keep one's footing.

Water that was inside a "level" lake (or even an ocean for that matter) would feel that the lake was spilled over by 45 degrees towards the East. The water would spill over and 'fall downhill' over flat land.

In fact, you would need a west-facing slope steeper (BBB) than 45 degrees to retain any water. Some of the oceanic trenches may be able to retain some water.

As you move away from the Equator, the BBB eastward speed is less than at the equator. It is a function of the cosine of latitude.

At latitude 45 (North or South, same thing), it is 328 m/s.
lateral deceleration would be 6.9 m/s^2
At latitude 60, it is 232 m/s. Deceleration 4.9 m/s^2
At the poles (latitude 90) it is 0. No lateral deceleration

In all these places, Earth's gravity is still 9.8 m/s^2 towards Earth's centre, but the deceleration due to braking is less. At the pole, there is none, so any water puddle, lake, ocean near a pole does not get spilled. Eskimos are not thrown to the ground.

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The Earth is massive. All the rotational energy would have to become some other form of energy (very likely: heat).

Earth's rotational energy is 2.58x10^29 Joules.
If you release all that energy in 47.4 seconds, that is the same as having a 5.4x10^27 Watt heater, on for 47.4 seconds.

To give you an idea, that is 14 times the energy output of the Sun. The Total output of the Sun. Fourteen times 3.85x10^26 W.

I dare say that it might heat up the Earth...
... quite a bit.

Depending how deeply this heat was to be released, it may take some time before we are cooked and/or before Earth's surface is habitable again. That is the part that would make it hard on all of us (regardless of latitude).

Answer 9

Because of the huge temperature contrast between the light and dark sides, massive storms would develop along and around the boundary region. If you also assume the earth has a zero tilt, the band would increase in width over the light region, and decrease in width over the dark region as latitude increases.

Answer 10

Besides the one side frying, one side freezing thing (which is correct), before that happened, everyone near the equator would find themselves moving eastward at about 1,000 mph, people in the continental U.S. would find themselves moving east at between 600 and 800 mph (depending on their latitude), and people nearest the poles would'nt notice anything at all besides the fact that the sun stopped moving. So in short, if the earth suddeny stopped rotating pretty much everyone would die.