why? is it gravity has no poles?
85499
Gravity is always attractive.  For a force to have poles, in the sense that I take it you mean, it must be sometimes attractive and sometimes repulsive.  A magnet is said to have poles because it has one end that repels the like ends and attracts the opposite ends of other magnets.  Gravity doesn't do this; it attracts everything, so there is no way to establish a gravitational  "North end" and "South end."\n\nNow, in another way of looking at it, every bit of matter could be considered to be a "gravitational monopole", just as static charges are electric monopoles.
46266
When it is said that that the net force is zero, it means yes, there is gravitational forces acting at the cenetr of the earth, but being at the center, with equal amounts of earth mass in every direction, the forces pulling on you at the center would all cancel each other out, resulting in the <perception> of having no forces acting on you, when in reality, gravity is always at work.
141031
because the earth is causing the gravity... everything in space has gravity. How much gravity depends on the objects mass. Bigger mass bigger gavitational pull.
42159
I'd love to know what your answer is. Its actually something physics seems very confused about.\n\nAccording to GR, its masses that cause the curvature of space. Gravity isn't a force, its just masses following the path of least resistence - straight lines in curved space time.\n\nThe problem is they then try to introduce gravitons to carry what isn't really a force. Very confusing.\n\nIf we assume Einstein is right, that gravity isn't a force, but masses following curves, the real question becomes - where does mass come from?\n\nMy guess - quantum entanglement create at time zero that keeps everything in the universe interacting. I don't like the higgs bogusons theory, since that introduces yet another force carries in the terms of a, erm, massive particle that gets mass from, erm, itself...
1090868
Yeah there's no actual land up there.  And these is also a magnetic north/south poles as well as the geographical north and south poles.
357562
What is this gravity that you mention?  :P\n\nGood point tho, funny how it didn't exist until very recently in our history.  *hugs*
12149
****Edit based on further details from asker *****\nSailing around the world is sailing within the sperhical confines of our planet.  If there were no athmosphere, or gravity, then we would simply fall off the earth.  However, as gravity is pushing us down, and is affecting the winds, ect within the athmosphere, we are bound to the surface of the water.  \n\nEven though a sphere is included in the define of spheroid, it is a type of spheroid, not the inclusive answer.  The fact that gravity pushes down on us from all around, mainly because the earth is spinning so fast, and other more complicated reasons; the sphereoid holds whatever is on it's surface down to adhere to the confines and shape of such a surface.\n\nEven if the world were flat, or a flattned sphereoid, we woudln't fall off, instead, we'd loop around to the otherside becasue gravity wouldn't allow us to actually 'drop' off the side of the cliff.  The inverse gravity on the other side of the plane would pull us to it's confine, or surface.\n\nSo, there's your answer.  Sorry i didn't get it more clear the first time.\n\nMathamatically you can say that gravity pushes us from all around using a tangent direction.  That means that no matter the point you are on this earth, gravity is pushing down on you within the same confines as any other like region.  As to falling off the earth, if gravity didn't exist, we wouldn't 'fall' exactly; we would more likely be thrown or float off the earth (thrown if the world is spinning).\n\n****End Edit.******\n\nThe world indeed is a sphere, but it is not a perfect sphere, due to the rotation of the earth around it's axis, as well as the rotation of the earth around the sun (central axis), the spinning and speed of the planet make it more of a spehere that jiggles, sometimes squeezed, and sometimes elongated.  But, not by much :) Just a bit :)
540592
Gravity is not caused by magnets. It is caused by matter itself, but it only happens noticably when theres a LOT of matter together (the earth is a LOT of matter).\n\nWe dont really know why matter causes gravity. We cant even measure gravity waves, but we're trying.\n\nString theory is a mathematical system which tries to explain gravity. I dont understand any of it, but thats what people who want to understand gravity are studying.
1169302
Yes, gravity exists near anything that has mass.  If you remove the air from a container, what's inside won't float.
48086
Sometimes, you weigh less, gravity's pull does not change, doy!
13005
Its because physics seems to be really confused about this issue. We're all taught that Gravity is a force of attraction between masses. However, when you look at General Relativity you find that it is not. It is the warping of space-time by mass that causes masses to follow curved geometries that make it look like there is a force acting between them. Where it is really confusing is that then they say that Gravity is transmitted through gravitons - which seems counter intuitive to the whole GR scene. I think that's why Physics is still struggling to find a GUT (Grand Unified Theory) - they are trying to shoe-horn gravity into a place it doesn't belong.
248052
its the same as why does gravity not apply in the subatomic...when we know the answer a new dawning in science will amaze the world...
801793
and gravity does what?\n\nand why don't you fall off?
511616
First: Gravity is due to mass, while magnetism is due to the movement of an electric charge.  For earth, this is believed to be caused by the movement of ions within the earth, the magma near the core.\n\nSecond: The poles of a magnet were misnamed.  They named the poles of a magnet because of the direction they pointed.  However, once the properties of magnetism were truly understood, it was too late.  So, appropriately, it could be said that near the north pole is the south magnetic pole, but I'm sure most teachers would frown upon that assertion.\n\nOther notes about magnetism on earth: The earth is imperfect.  The magnetic field is not uniform, so there are variations.  Magnetic north is not geographic north in all situations.  The earth is tilted, and we don't really know the flow of the magma that causes the magnetic field all that well.  Not to mention, there is speculation that magnetic north and south may flip at some point in time, but the mechanism of this is lost on me.  It has happened a very long time ago, and is expected to happen again sometime in the future.
1064567
any object in space floats due to the absence of gravity.so,the flag also must be floating.the moon had a surface in which the flag was landed
955624
If it wasn't for gravity, there would be no earth.  (Gravity holds the earth together.)  \n\nThe very notion of "up" and "down" *needs* gravity, or it has no meaning.  The very notion of "down" has always meant,  "in the direction of gravity", even before we knew what gravity was.  If you are in a room with no windows, how do you know which way is "down"?  Because "down" is THE DIRECTION THAT THINGS FALL.  When you stand up, it's THE DIRECTION OF YOUR FEET.  Without gravity, there is no notion of falling, and no notion of "standing up" so "down" (and "up") have no meaning.  Think of astronauts in a room with no windows on the Space Station.  They have no "up" or "down". \n\nOr think of it another way.  The notion of "up" and "down" has less to do with the direction of the earth, as with the direction of gravity.  If you are standing on the moon, or on mars, which way is "down"?  It will be in the direction things fall ... towards the planet you are standing on.  So "down" is defined relative to the current direction of gravity, regardless of what is causing that gravity.\n\nSo the earth has no "up" and "down" except with respect to gravity.  It also has no "top" or "bottom" ... the North Pole is not the top of the earth.  We just like to make maps that way, but there's no scientific reason for it.    (The Egyptions drew maps relative to the Nile river ... so the "upper Nile" is South, and the "lower Nile" is North.)
623233
It's gravity that keeps everything in place. And ya'll, don't be hatin' on this persn, it's just a question!