Why is gravity so weak? - from Alex - 2 answer(s)?
961066
Your right - gravity is ludicrously weak. The force of gravity of the entire earth on your body is held back by the electrostatic force of a single layer of atoms in your shoes. Gravity is weaker by many orders of magnitude than every other force in the universe.\n\nAnd its a good job it is. Because otherwise we would not exist. \n\nHowever, we have no theory as yet that explains the relative magnitude of forces. It is considered one of the failings of the theories of physics - the parameters that determine the magnitude of the forces simply have to be fed into the equations from observation.
300802
if the point is big the gravity don't effect it much but if it is small gravity will effect it i forgot the whole explanation though \n\nyou could try this link
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*
954663
it has gravity indeed, but less than earth\n\n:> peace\n.
171241
The previous answer explained very well why it is important that the strong and weak forces are stronger than the electromagnetic force.  I will address *why* it's a good thing that gravity is weaker than the electromagnetic force, which also extends to an infinite distance.  That is because, while the electromagnetic force is sometimes attractive, sometimes repulsive, depending on the charges involved, gravity is always attractive.  Thus, while the electromagnetic force between any two fundamental charged particles is comparatively strong, overall, electromagnetism is weak, because the attractive and repulsive forces balance out.  Another way of saying the same thing is to note that overall, most macroscopic objects are electrically neutral, they have an equal number of positive and negative charges.  Even highly "charged" objects have overall only a tiny percentage more of positive charges than negative charges, or vice versa.  If gravity were as strong as E.M., then the universe would quickly collapse (or more properly, never would have formed) as all the particles in it would be too tightly bound together.
1178364
Where do people get the idea that the rotation of the earth causes gravity?  There is gravity because every mass in the universe attracts every other mass. Spinning has nothing to do with it. The magnetic poles don't have anything to do with causing gravity either.\n\nDoesn't anyone study science?
1053103
Podkletnov has demonstrated a number of laboratory devices that supposedly work by antigravity.  I'm not sure what he's claiming lately, but his original work claimed a reduction in gravitational force of 2%. So far, apparently, no one has been able to replicate his results.\n\nAlso, in the absence of a solid theoretical analysis, it is possible that he is really generating some other type of force. For example, T. Townsend Brown's "lifters", long a favorite of antigravity hobbyists, are actually ion wind devices.
729210
They have energy, and gravity depends on stress-energy not simply mass. However, the gravitational interaction would be exceedingly week.\n\nThey also polarise the vacuum state and so can scatter via the electrostatic interaction. This again would be a very tiny effect and has never been detected, though proposals for experiments exist - see link.
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.
1000866
that's why mass is not wieght, it is not dependent on gravity. so yes
1165783
It is wrong to say that there is no gravity in space. This is why you hear astronauts use the term "microgravity".\n\nGravity is a property of mass. All objects have mass and thus attract other objects with mass. It takes a lot of mass for this effect to be noticable. Here on Earth, the Earth is massive enough that we notice it! Gravity holds us too the Earth. The farther you go from the center of the Earth, the weaker the gravity becomes. For example, the pull of gravity is slighty slightly weaker on Mt. Everest than it is at the beach.\n\nYou'd have to go very far into space for this pull to become half as strong as it is here on Earth. \n\nThe reason astronauts and other things in orbit float is because they are in a perpetual state of free fall do to the fact that the Earth is curved and they are traveling around it at such great speeds that for every foot they fall towards the ground, they move over the horizon just enough that the ground doesn't have a chance to get closer. If the astronauts remained stationary over one point on Earth then they would fall to the ground.\n\nThis is true for anything in any stable orbit. If the Earth were to stop moving around the sun for some reason, it'd fall into the sun.\n\nThere ARE points in space where we can say gravity due to the net force of two or more objects is zero. If you were traveling between the Earth and Moon, or the Earth and Mars, or any two massive celestial bodies, you will find a point where the pull from one body is equal and opposite to the pull from the other body. This is like a balancing point. A little closer to the Moon and that becomes the object which you're falling towards, and a little closer to Earth and that becomes the object which you're falling towards.\n\nThere is also theoretically a distance in space where you could be so far away from anything that the pull of gravity on you is negligable....but not zero.\n\nSo in space you are actually always falling towards something. Comets enering the solar system are ultimately falling towards the sun. The astronauts are falling towards Earth without actually getting any closer, the Earth is falling towards the sun without getting any closdr, the sun is falling towards the center of the galaxy without getting any closer. \n\nI hope you get the idea.
134909
Alas, another one of our many unanswered questions... It's possible that Newton could have been wrong about just one thing, or perhaps there is something intelligent out there to cause it to happen... Or perhaps it was the force from some exploding star, or black hole...
280881
There isn't gravity "on the moon"; gravity is a property of objects. And the self-congratulatory tone of the guy who says you must have realized that your premise is wrong betrays the fact that his answer is a tautology. The only reason the moon exerts a gravitational pull is BECAUSE of its mass. If there were no mass, there would be no gravity in the first place. One can overcome the force of gravity, but saying that the moon would fly apart without it doesn't make any sense. Gravity will be there no matter what. Other forces can overcome it (otherwise the Apollo astronauts who landed there wouldn't have been able to leave its surface), but gravity can't be turned on and off.  In a less dramatic way, one could see the astronauts picking up rocks, or kicking up dust. The kinetic energy of their movements was enough to overcome the force of gravity on the moon until the dust settled (which it does much more quickly than it would on earth, since the dust doesn't encounter friction with air).\n\nNo one knows exactly what gravity IS, by the way. Some physicists believe that it results from the warping of space-time; others continue to seek out a particle (the "graviton") that is the conduit of the force (kind of like "photons" are particles of light).
1068102
Gravity may only be a theory, but we have a good idea that it is real. We may not know the exact workings of gravity, but we know it is there.\n\nGravity affects everything. It affects all the planets, it's what makes us revolve around the sun. I'm sure the 'devil' has nothing to do with making sure all the planets get around the sun. It's trivial, and you're theory is even worse than the theory of gravity because it has absolutely no backing. We can see gravity and it's effects everyday. Scientists don't know all about it, but for the most part, we know it's real. Your theory on the other hand, there is no proof of the devil. He's a made up character, fake. Then to say he pulls us down, you forgot to take into consideration everything else effected by gravity, not just humans. \n\nIf the devil is pulling us down so effectively, he must be extremely strong. Where is your God to pull us up? Shouldn't He be able to pull us up, if He is so great? Nope, still not happening.\n\nTheory disproved. Face it, religion plays no part in science. Religion's purpose is to make people feel good about themselves, and provide answers to the answerless (such as creation). Science is out to prove what happened, and religion serves as a temporary explanation for most.
49395
There is a confusion about magnetic attration and gravity attraction. First of all,nothing has been proven to show that there is something in the earth that pulls you down.It makes more senseto believe that gravity is an external phenomena rather than an internal one.\n\nThere is no magnetic response unless two poles exist in a material. In this case we have an internal phenomena which has to do the atomic structure of the material which forms\nan external circuit of twisted space. It requires two opposite ends to observe a magnetic response. The poles of a material which is magnetized can exhibit both attraction and repulsion.\nMost material display some magnetism.\nFerrous material are able to store magnetic power more so than other material because of the arrangement of their electronic structures.\n\nIt is believed by scientists that  the magnetism of the earth is caused by a molted iron core;however ,it has\nbeen shown that at high temperature a magnetic field cannot be established.\n\nThe best explanation presented was that the earth magnetic field is caused by the motion of the ocean around the earth.
1183764
But...blasting matter in the direction of gravity's pull IS propulsion! :)\n\nYou can't get any "work" without expending energy of some sort.  There's no way to move anything without using some sort of energy.  Perhaps one day that will involve anti-gravity devices, but they'll have to use anti-gravitons in some way to work, which will involve imparting energy to the anti-gravitrons, which will be propulsion (just a different kind).\n\nThe problem with gravity is that it's pretty weak compared to the other fundamental forces.  The weak nuclear force is millions of times stronger that gravity, which means its anti-force is also milltions of times stronger.  Gravity works well for pulling large masses together into planets and stars, but on a small local level it's not that usable...there will probably be better ways to getting about than anti-gravity.
113961
Simple explanation:\n- - - - - - - - - - - -\n\nThere are four fundamental forces that act on objects:\n\nGravity\nElectromagnetism\nWeak (responsible for radioactive decay)\nStrong (holds the nucleus together)\n\nFrom Newton's 2nd law, a force F= m a where m is the mass of the object and a is its acceleration (acceleration describes how an object changes speed, so it has to do with movement of the object). \n\nGravity is one of the 4 possible choices for F. So when the force of gravity exists, things accelerate, according to Newton's 2nd law. \n\nDeeper Exploration:\n- - - - - - - - - - - - - \n\nOne can ask the question, but WHY does gravity create a force? Einstein described it in the general theory of relativity as a bending of the space we live in (called spacetime: 3 space dimensions and one time dimension), and then specified that objects are required to take the shortest path in this curved space. \n\nHowever, that still does not describe WHY gravity does this. Current belief (but not yet proved) is that two objects with mass exchange messenger particles called gravitons (not yet observed) that communicate the force of gravity between then (electromagnetism has photons, or light as messenger particles, weak and strong forces also have messenger particles, so people think that gravity should as well). \n\nAnother interesting thread of thought in physics is that all 4 of the four fundamental forces are aspects of the same thing (just like electricity and magnetism are aspects of the same thing). So far, weak forces and electromagnetism have been shown to have the same origin when looked at in the right way, and it is possible that the strong force has the same origin as well (called a Grand Unified Theory, or GUT). Physicists are trying to find a framework whereby all 4 forces are aspects of the same universal force (called a Theory of Everything, or TOE).\n\nHowever, one can still ask, why is it this way? Well, although we have a few theories here and there, very little is proven, and the basic bottom line is, we do not know WHY gravity makes things move. \n\nBut we have a lot of clues and equations and we can make very accurate predictions for how gravity works in many cases.