Why  is gravity talked about as an absolute pulling force,when force is not absolute?
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.
939985
Well, yes, the gavity is pulling you down, and you are not moving. So you are subjected to an acceleration and are not moving.\nMind you, one can argue that the *resulting* force is zero, as the ground is reacting with an equal and opposite force to your weight; if you take it that way, to have an unbalanced force should result in motion.
904747
Its origins and nature are still open to postulation. But it is an attractive force only between any two masses and Newton concluded in his uneiversal laws of gravitation that the attractive force (F) was proportional to the masses interacting(M1 and M2) and inversely proportional to the square of their distance apart (r)\n\nie F α M1*M2/d²\nwhence \n\nF = G*M1*M2/r² \nwhere G is the universal gravitation constant\nG ≈ 6.6742 x 10^(-11) Nm²/kg²
918251
Uh... it contains mass but doesn't have the act of the pull of the earth?
596969
A push or a pull is a Force *vector*.  A push or pull at the same force would be equivalent length vectors, just in opposite directions.\n\nThe fact that they are vectors is important because pushing and pulling imply a direction to the application of the force.
909451
The energy per unit volume of a gravitational mass is the pressure holding the mass together. so if you multipy the gravitational pressure that hold the mass together by the area enveloping the gravitational mass you obtain the total force surounding the mass.\nAs Sherlock Holmes would say = "elementary...\nTherefore from this analysis we see that The gravitational force is proportional to the curvature of the gravitational mass which in turns causes a curvature of the space gravity field.\nAnd that is the whole principle of gravity.\nIt took me years to figure that one out.
261295
the force of gravity is one of the weakest (you can just see it's effects in a macroscale) that's because G is such a a small value... this Cavendish guy used a torsion balance to measure G ( a rod with two metal spheres at their ends).\n \nwhen you twisted the rod, then a torsional force is exert (..that force is proportional to the angle of rotation of the rod) ; He relate the angle of rotation and the quantity of torsional force ..then, he brought 2 lead spheres near the smaller ones (attached to the rod) ..because the force of gravity the larger spheres attract the smaller ones , twisting the rod ..then he measured how much..he knew F, and the masses of the metal spheres , then by Newton's formula F=Mm/d^2 ( he knew d ..the rod lenght) he determined G...the first experimental measure of G (maybe he didn't have a life :).\nI've found also this page that may help you, good luck
169921
shosh is correct. Cause they are! The pull of gravity comes from the earth. Don't get hung up on UP and DOWN. There is no UP or DOWN... What is UP? Why would you assume that you are UP and I am DOWN? Or vise versa? There is no UP or DOWN. We have just chosen north as up as a convenience. You could hold a map in any direction or a globe at any angle it doesn't matter. We just have tried to standardize our thinking. We are working with a 1000 year old model that doesn't take into account what we know today.
48086
Sometimes, you weigh less, gravity's pull does not change, doy!
404666
By the pull of earth's gravity
208985
The force of gravity has to do with an attraction of objects due to mass. The nuclear force has to do with attraction or repulsion of nucleous at very small distances. Electric Force is attraction or repulsion due to the charge of the object, and is very important in the actual structure of an atom. Inertia has to do with the continued movement of an object (an object in motion continues to move unless another force acts upon that object.)\n\nYou might think that gravity is a strong force, because you see it's effects all the time - however, the strongest forces will either be the nuclear force or electric force. If gravity is stronger than electric force, then you get black holes.
1114940
Pressure can't be associated with a direction coz it is directed in many directions simultaneously. Weight is a vector coz it the gravitational pull that  is always directed towards th centre of earth.
607637
Centrifugal force is  a virtual force. I wonder if it is just an outcome of Newton's absolute space. Since absolute space is not valid concept so is the centrifugal force. So You decide , whether you wanna go to find the quantum mechanical expalnation of the another blunder!
21267
Gravity is the force of attraction between massive particles. Weight is determined by the mass of an object and its location in a gravitational field. While a great deal is known about the properties of gravity, the ultimate cause of the gravitational force remains an open question. General relativity is the most successful theory of gravitation to date. It postulates that mass and energy curve space-time, resulting in the phenomenon known as gravity.\n\nGravity is acceleration.  means that (if the mass is unvarying) there must be a force that causes a mass to accelerate. For a rocket ship, that is the rocket engine. For the earth, it is the compression of the mass between something on the surface of the earth and the earth's center of mass. The acceleration is in relation to spacetime in that the weight one feels is one's resistance to deviating from one's path in spacetime. The same holds true in the rocket ship except that a rocket engine supplies the force to accelerate an occupant from his spacetime path. There is no difference between the weight he feels because of gravity or the rocket.
36927
Anti-gravity in the context of mainstream physics\nNewton's Law of Gravitation considered gravity to be a force between two objects, causing attraction in proportion to the objects' mass. Under this interpretation, an object with negative mass would repel ordinary matter, and could be used to produce an anti-gravity effect. Alternatively, depending on the mechanism assumed to underlie the gravitational force, it may seem reasonable to postulate a material that shields against gravity or otherwise interferes with the force. An example of such a material, cavorite, is a major deus ex machina of H. G. Wells' famous book, The First Men in the Moon, though it should be noted that Cavorite isn't consistent with even a Newtonian view of the universe (it causes violations of conservation laws). Neither negative-mass exotic matter nor a gravity-screening material have been observed experimentally. While the potential existence of exotic matter is still debated, general relativity presents persuasive arguments against the existence of screening materials. \nEinstein's theory of general relativity, published in 1915, supplanted Newton's model of gravity with an entirely different mechanism - one based entirely on the geometry of the universe. Gravity was no longer a force at all, but simply the consequence of the local slope of the universe in a direction the human eye cannot see: time. You stick to the floor not because gravity is pulling you down, but because that is the shortest distance between today and tomorrow. Under this model, gravity in a universe containing only matter with positive mass is purely attractive. No arrangement of ordinary matter can produce an anti-gravity effect. Spacetime geometries corresponding to true anti-gravity in general relativity require negative mass. \nSome models of anti-gravity claim to derive from general relativity.\n\nThe model of gravity proposed by the theory of general relativity breaks down under extreme conditions (too far inside a black hole, and in the very early life of the universe under the big bang model). In particular, most physicists believe that at extremely high energies, gravity and the other fundamental forces unify, which would allow gravity to be manipulated in ways that are not readily apparent now. Candidate models for this regime are theories of everything, which attempt to model all four forces (example: string theory), and theories of quantum gravity, which attempt to produce a model of gravity that is consistent with quantum mechanics, though not necessarily unified with the other forces. \nSome models of anti-gravity claim to be based on quantum gravity models, though the connection of these to mainstream quantum gravity models is often tenuous.\n\nConventional effects that look like anti-gravity\nMagnetic levitation suspends an object against gravity by use of electromagnetic effects. While visually impressive, this is not an anti-gravity effect. \nCritics of various alleged anti-gravity devices often suggest that unusual effects observed around them are due to electromagnetism.\n\nA tidal force causes objects to move along diverging paths near a massive body (such as a planet or star), producing effects that seem like repulsion or disruptive forces when observed locally. This is not anti-gravity. In Newtonian mechanics, the tidal force is the effect of the larger object's gravitational force being different at the differing locations of the diverging bodies. In Einsteinian gravity, the tidal force is the effect of the diverging bodies following different paths in the negatively curved spacetime around the larger body. \nLarge amounts of normal matter can be used to produce a gravitational field that compensates for the effects of another gravitational field, though the entire assembly will still be attracted to the source of the larger field. Physicist Robert L. Forward proposed using lumps of degenerate matter to locally compensate for th
1123435
Hi, its not gravity but a force opposite to gravity that prevents a boat from sinking and keeps an airplane in the air. Sorry, but I forgot the name of the force, I think it begins with a B. O, the second person said it- Buoyancy.
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?