Does gravity have anything to do with a planet spinning?
365770
i dont' know what causes the rotation of an orbiting planet, but the moon would definitely have gravity even if it didn't spin.  that dude was full of crap.  if anything, the spin would cause things to fly off.
611220
This is about conservation of momentum. Any object on a rotating (and for our experiment atmosphere-less) planet has the same rotational momentum and angular velocity  as the surface. If it jups up, it will increase the radius, and therefore reduce the angular velocity, so it will land further behind.
180202
Neither. It's the mass of the planet itself. Everything that has mass projects a gravitational field. The more massive an object is, the bigger its gravitational "pull". This is why objects like the Sun can support several large planets, while Pluto (which has a moon about a third the size of it) gets pulled around by its moon.
320933
Two reasons:\n\nPrimary = spinning + gravity = natural inclination of the material to slowly reach equilibrium. Anything that is not "round" gets pulled/shifted toward the center of gravity (the center of the Earth). The spinning helps this process over billions of years.\n\nSecondary = weather. Erosion constantly smoothing out "bumps" (mountains).\n\nIf this is the best answer, please vote it the best answer. Thanks!
1086242
I think all "matters" that spin have magnetic field. I believe magnetic field is basically causing earth to have north and south pole, allowing it to spin on its axis. Earth's moon, any moon, even Sun rotates, so, it's like all planets, stars, and moons have magnetic field.
108530
Not all the planets do rotate on their axes with constant angular velocity (see reference) and even two rotate in the opposite direction to earth (counter clockwise when viewed from the celestial north pole); venus and uranus (called retrograde motion). \n\nThe rough alignment of all the angular momentum vectors in the solar system, including orbital and rotational angular momenta of all the planets, moons and the sun is presumably a left over relic from the angular momentum when the system was formed from a rotating gaseous collection of material.
237936
You say "when" like you think it is going to happen any minute.\n\nThe acceleration due to gravity does not depend on the rotation of the Earth, it only depends on the mass of the Earth and the distance from it.  No matter how fast you are traveling or the Earth is spinning, there will alwasy be a constant gravitational attraction between the Earth and some mass at a constant distance.\n\nHowever, the fact that the Earth is spinning has the effect of lowering the percieved influence of gravity in a way.\nGravity can be through of in this case as the centripetal force which is causing you travel in circular motion.\nWithout going into too much detail (and I fear that I am not explaining it clearly), the force of gravity can only cause so much of a centripetal acceleration, beyond that and you cannot continue in the same circular path.\n\nThere is a point where the force of gravity would not be enough to "hold you down" if the Earth was spinning fast enough.  You set your weight (weight = force of gravity) eqaul to the centripetal force (the force causing you to moving in circular motion), then you can solve for the tangential speed of the Earth's rotation which you would be "weightless".\nHowever, the force of gravity in and of itself is in no way effected by the Earth's rotation.\n\nI hope I explained it clearly enough, this topic lends itself to people using in correct terms like "centrifugal force" which is really not correct.
446986
Yes, it does, but by a very negligible amount.\n\nDue to the law of conservation of angular momentum, the Earth has some over all value for its angular momentum (and for that matter, so does the solar system and our entire galaxy, ... as well).  As thr plane is flying around the Earth, it has some angular momentum too, different from its original value just sitting still on the surface.  In order for the overall angular momentum of the Earth to remain constant, the Earth's rotation is effected ever so slightly.\nHowever, the effect is so small, it is not even noticible when we are talking about objects as miniscule as an air plane compared to the Earth.\nAlso, since, over all, on average, for every plane flying one way, there is another plane flying the other way (or when the plane returns), so the effects are all canceled out.\n\nIt is the same principle at work is your on a merry-go-round and you move closer in to the center or farther away (or in this case, around while spinning on the merry go round), angular momentum needs to be conserved, it is the law.
805592
first: by world, do you mean earth? \nIf so, think about all things spinning, are they not always more or less round or oval shaped? Actually so is the earth. \nOn the other way,I think that by spinning, a lot of things get that shape. Especially as like the stars and planets, they tend not to be in a fully finish state. Ok, that is my answer but I am no astronom only a nurse... MC
337086
The planets are actually trying to move in a straight line at a high speed due to the intertia from some force long ago.  When two objects are moving by each other, their gravity interacts and pulls them toward each other, bending the path that would otherwise be a straight line.  If they are too massive and too close, the gravity pulls them so much that they collide.  If things are balanced just right, the path is bent into a complete ellipse.  It's an ellipse instead of a circle because the sun is actually also being pulled a tiny bit toward the earth, as well.\n\nYou could consider gravity to be sort of a "perpendicular inertia", and the planets would revolve around the sun FOREVER if there were no other forces involved.
565295
Gravity is created by objects. "Down" is towards the center of the earth, where gravity is strongest. All planets, stars, asteroids, etc. have gravity.
755454
I answered this yesterday, but...\n\nWhat makes the Earth Spin...\n\nAngular Momentum. Think of a figure skater pulling their arms closer to their body while spinning, sudennly they are spinning VERY fast, then they let their arms out, and they slow down. This is because the arms still have the same amount of rotational energy as they did when they were further from the body, but when they are pulled close, they don't have as far to go to complete one rotation... the radius and circumference are smaller but the distance covered is the same over the same amount of time. This means faster rotation.\n\nHow does that have anything to do with the Earth? Simple. When the Earth formed, it formed by collecting bits of matter from space, and these bits of matter, ranging from dust to huge asteroids and larger, were all like tiny arms, adding rotational energy to the earth as they came in closer and stuck. \n\nRight now, the moon is slowing the earth's rotation as it slowly moves away from the Earth--again, this is the same process. How can this be when the moon doesn't even touch the Earth? Gravity. Gravity makes the earth and moon behave almost as if they were touching. The short explanation is that the center of gravity of the earth-moon system lies just below the surface of the earth, causing tides. Since the moon is moving away, it requires less orbital velocity to maintain it's orbit, and so the tides slow the earth more as the moon's orbital speed slows.\n\nEventually, the earth and Moon may both be tide-locked to each other, and this will happen long before the earth is tide locked to the sun (the tides have slowed rotation of the earth to the point where it always has one side facing the moon (or sun)).\n\nWhat makes the earth not stop spinning?\n\nAs mentioned before, angular momentum. The earth's surface can be slowed, but that energy has to go somewhere--it goes to speeding up the orbital velocity of the moon, which is why the moon is moving further from the earth...\n\nThe earth is moving around the sun because of the way the sun and all the other stuff in the solar system formed--from a cloud of gas and dust that collapsed into a spinning disk. The mechanics of the whole thing is still being learned and debated. As long as the Earth keeps moving in a straight line perpendicular to a line drawn between the Earth and the Sun, the Earth will continue to fall toward the Sun (by gravity) at exactly the same speed that it is flying perpendicular, and thus, like a ball on a string, it will follow a curved path around the sun.
310151
The Coriolis effect. If the Earth were not rotating, the effect would be a mysterious "fifth force" with no physical explanation. See the source for details. \nAccelerating frames are absolutely determined. The above references to relativity theory are completely incorrect; Newtonian theory equates frames with constant velocity, Einstein equates an accelerating frame with a local curvature (gravitation). This is all the two theories have to do with the badly referenced quotations above.\nThe amount of pseudoscience and bad science on these forums is strange, given the amount of knowledge freely available over the internet.
991785
The gravity force depends on the mass of the object. For gravitational force, rotation of an object doesn't matter, it will always pull to the centre of mass.\n\nRotational momentum can cause objects to be thrown off if the momentum causes a movement which exceeds escape velocity. Escape velocity depends on the mass centre.\n\nA spinning ball simply has a very low escape velocity. If you spun a ball so it rotates once every 24 hours, things probably wouldn't be thrown off, either.
267938
Eventually, when energy expendure costs the sun enough mass, according to Newton´s gravitational law, the earth would move away from the sun, but if earth keeps the same orbit (the spin for this matter in irrelevant), it could not be a case where the planet moves away.  It could be compensated by the gravitational pull of other planets and instead og going further away it could simply speed up a little.
799364
Ask your son to turn around in a circle once per day.  That is the rate  of the earth spinning.   One rotation per day.  Did he get dizzy?  \n\nSpinning is angular speed or angular frequency( the rate it turns through an angle), not the speed, tangent to the circumference of the earth.\n\nThe earth spinning is improperly linked to 1000 mph.  The earth spins one time per day.  The surface velocity is 1000mph at the outer surface of the earth, but that is just like going straight at 1000mph.\n\nThe surface speed of the earth is undetectably with out a frame of reference.  Just as speeding in a car...without looking out the window, you don't know if you are moving that fast.  We only detect a change, acceleration.  The earth spins so slowly, we don't detect the angular frequency as being dizzy.
914874
yes if it is spinning on its own axis as it moves.  This is called Spin Angular Momentum