Is the gravity force a MonoForce?
408403
Magnetic forces, electric forces are bi-polar: there are North and South poles on magnets, as well as positive and negative charges. As a result the forces can be attractive or repulsive.\n\nGravity is mono-polar in the sense that the force between two masses is always attractive.
643953
depends on the direction of the force
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).
1060580
No.\n\nOnly gravity can be interpreted as a curvature in space-time. This is because only gravity acts on all particles - with or without rest mass. All other forces act specifically between particular types of particles.\n\nYes, space-time ripples. General relativity's equations have wave like solutions that predict that changes in the mass/stress producing a gravitational field will propogate in a wave like manner.
1000866
that's why mass is not wieght, it is not dependent on gravity. so yes
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.
324067
No. Gravity has to do with the mass of objects--you have some too.
734596
A force at its most simplistic is a push or a pull. According to Newton's laws of motion, when something is at rest or travelling at constant velocity, there is NO force acting on it. \n\nNewton's second law states that Force = mass x acceleration which means that a force causes a _change_ in velocity (acceleration). So for continuing motion, there is only a force when there is acceleration.
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.
939446
It is strong enough - the astronauts didn't go floating off. It is weaker, which is why they were able to take such big steps, but in order to leave the moon they had to take off in the lunar lander...\n\nThe interesting thing about gravity as a force is that it's quite weak compared to other forces like electromagnetism and the nuclear forces, but that it works over huge distances (unlike the other ones). This is why the moon has an effect on the earth, but at the same time we can easily counteract the effects of gravity - for example by standing up!
618210
Not due to gravitational pull?!
37677
its not really a type of force it's just a force that is balanced... like it's in equalibrium because it has another force of equal magnitude going in the opposite direction. such as if there was a 5N force pushing into a wall, it's a balanced force because the system is in equilibrium and the wall is pushing back with a force of 5N.  or if you were pulling on a rope with 8N and it was a balanced force, that would mean that someone else was also pulling with 8N and you aren't going anywhere.\n\nWhen the forces are balanced, that means that there is no net force. this means that whatever the forces are acting on is not experiencing any acceleration, so it's either at rest or moving with a constant velocity(no acceleration).
1178122
A force is conservative if it can be described as the gradient of a scalar potential. So for instance gravity is conservative because it is proportional to the gradient of the gravitational potential energy.
1184941
The force of gravity of one object on another is given by the equation\nF = (GMm)/r^2\n\nWhere G is the universal gravitational constant, M is the mass of one object, m is the mass of the other, and r is the distance between the two.\n\nYou can see that the greater the mass of the two objects, the stronger the force of one on the other is.\n\nIn short, things that are more massive get a better tug.
658894
Gravity is a property of all particles that possess mass. It is just a fundamental force that at the present can not be explained scientifically to a complete extent.\n\nAny particle that possesses mass (which is basically everything apart from light) has its own gravitational potential which stretches off into infinity. Any other mass which enters this field is subjected to a mutually equivalent force. Obviously then, all matter in the universe is simultaneously interacting with all other mass\n\nIt is proposed that a particle called the graviton carries the force between all massive particles, however this has yet to be identified.\n\nAnother theory is that gravitational waves are constantly being emitted by all objects, and these carry forces.\n\nEinstein proved in his general relativity paper that the presence of mass curves space time and what we observe as a force is merely a particle taking the shortest route through space. This is the current view of gravity\n\nGravity is made purely by the presence of mass, exactly what 'form' it takes is not yet proved.
345655
Gravity is also like another force. it follows Newton's 3rd law. Earth attracts us and we attract Earth.\n\nBut a = f/m. Since our mass is less, we move with greater acceleration. For earth, mass is huge and the effect is negligible.
345992
Yes. The gravitational force is not that weak.\nNote also that the pressure difference is not sudden at all, higher and higher into the atmosphere, the pressure becomes lower as the weight of the particles above becomes less. As the pressure gets lower, the effect of gravity is also lower.\nWe do still lose some air particles into space, but not a significant quantity.