Rahman Posted September 21, 2015 Share Posted September 21, 2015 What kind of force in the gravitation is any realation with magnetism ? can we create artificial anti gravitation on earth any possibilities??? Link to comment Share on other sites More sharing options...
swansont Posted September 21, 2015 Share Posted September 21, 2015 No, it is not related to magnetism, though the math that describes gravitation is similar to that found in electrodynamics. We cannot create anti-gravitation. Link to comment Share on other sites More sharing options...
Endy0816 Posted September 21, 2015 Share Posted September 21, 2015 Closest to anti-gravity we can come are different forms of magnetic levitation. Link to comment Share on other sites More sharing options...
swansont Posted September 21, 2015 Share Posted September 21, 2015 Closest to anti-gravity we can come are different forms of magnetic levitation. Not sure why magnetic levitation is any closer than stairs, an elevator/lift, or rockets. Or even just standing up. Those are all examples of some other force coming into play, directed opposite to the direction of gravity, and in no way examples of antigravity. 2 Link to comment Share on other sites More sharing options...
Endy0816 Posted September 21, 2015 Share Posted September 21, 2015 Not sure why magnetic levitation is any closer than stairs, an elevator/lift, or rockets. Or even just standing up. Those are all examples of some other force coming into play, directed opposite to the direction of gravity, and in no way examples of antigravity. Knew I should have added "in terms of appearance". Mainly thinking how people are fascinated by the likes of floating frogs and Hendos, but if you suspended a frog via strings or offered people a 5 minute skateboard ride for $100 the reactions will be very different. Link to comment Share on other sites More sharing options...
John Cuthber Posted September 21, 2015 Share Posted September 21, 2015 Currently sitting on an "anti gravity" chair. Should I get a job in advertising? Link to comment Share on other sites More sharing options...
michel123456 Posted September 21, 2015 Share Posted September 21, 2015 the fact that some other force (your chair) can act against gravity should mean that there exist a relation between these 2 forces. I mean, you can sit on your chair because the bindings of your body are similar to the bindings of the chair in such a way that you are not "transparent" to the chair. The action-reaction takes place, triggered by gravity.However, gravity is also "transparent" to you. I mean, you are not an obstacle (a shield) to gravity. You are influenced by gravity. I mean gravity exerts a force on your body. So there must exist some link between the bindings of your own body and gravity, but this link does not influence gravity on its action on other objects (it is transparent) Link to comment Share on other sites More sharing options...
swansont Posted September 21, 2015 Share Posted September 21, 2015 the fact that some other force (your chair) can act against gravity should mean that there exist a relation between these 2 forces. I mean, you can sit on your chair because the bindings of your body are similar to the bindings of the chair in such a way that you are not "transparent" to the chair. The action-reaction takes place, triggered by gravity.However, gravity is also "transparent" to you. I mean, you are not an obstacle (a shield) to gravity. You are influenced by gravity. I mean gravity exerts a force on your body. So there must exist some link between the bindings of your own body and gravity, but this link does not influence gravity on its action on other objects (it is transparent) The force the chair exerts has no "knowledge" of the kind of force that is on you, causing you to exert the force on it. It could be gravity, it could be electromagnetic. Link to comment Share on other sites More sharing options...
John Cuthber Posted September 21, 2015 Share Posted September 21, 2015 the fact that some other force (your chair) can act against gravity should mean that there exist a relation between these 2 forces. I mean, you can sit on your chair because the bindings of your body are similar to the bindings of the chair in such a way that you are not "transparent" to the chair. The action-reaction takes place, triggered by gravity.However, gravity is also "transparent" to you. I mean, you are not an obstacle (a shield) to gravity. You are influenced by gravity. I mean gravity exerts a force on your body. So there must exist some link between the bindings of your own body and gravity, but this link does not influence gravity on its action on other objects (it is transparent) I forgot to mention that I'm currently in interstellar space, but I can still sit in my chair because the motors driving my ship are accelerating me at roughly 10 m/s/s Fortunately for me, the chair is still able to offer a force that ensures that I carry on accelerating with my ship, rather than " falling through the floor". Link to comment Share on other sites More sharing options...
Sensei Posted September 22, 2015 Share Posted September 22, 2015 the fact that some other force (your chair) can act against gravity should mean that there exist a relation between these 2 forces. I mean, you can sit on your chair because the bindings of your body are similar to the bindings of the chair in such a way that you are not "transparent" to the chair. The action-reaction takes place, triggered by gravity.However, gravity is also "transparent" to you. I mean, you are not an obstacle (a shield) to gravity. You are influenced by gravity. I mean gravity exerts a force on your body. So there must exist some link between the bindings of your own body and gravity, but this link does not influence gravity on its action on other objects (it is transparent) You're also source of gravity. If below ground there is large amount of metal, say iron ore, it's influencing by tiny tiny amount gravitational acceleration g in that area. It can and is measured by f.e. oil&gas industry and used as information about "something is there" for further investigation. Map of how gravitational acceleration is varying is here https://en.wikipedia.org/wiki/Gravity_of_Earth Link to comment Share on other sites More sharing options...
michel123456 Posted September 22, 2015 Share Posted September 22, 2015 The force the chair exerts has no "knowledge" of the kind of force that is on you, causing you to exert the force on it. It could be gravity, it could be electromagnetic. Sure. What I was trying to say is that when different forces of different nature do combine that must mean that the forces interact, and thus have "something" in common. If they had absolutely no common interaction well then they would not ...interact. 1 Link to comment Share on other sites More sharing options...
swansont Posted September 22, 2015 Share Posted September 22, 2015 Sure. What I was trying to say is that when different forces of different nature do combine that must mean that the forces interact, and thus have "something" in common. If they had absolutely no common interaction well then they would not ...interact. Forces don't interact. An object in a chair exerting a force on the chair might be subject to a gravitational force, and/or an electrostatic force, and/or a magnetic one (or as John Cuthber points out, merely be accelerating). The chair itself does not have to be feeling any of those forces. It could be uncharged or made of a nonmagnetic material. We could be in a gravity-free region of space. The forces acting between two objects need not be the same as other forces acting on either of them. All we know is that if A exerts a force on B, B exerts the same kind of force on A. Link to comment Share on other sites More sharing options...
michel123456 Posted September 22, 2015 Share Posted September 22, 2015 (edited) Forces don't interact. An object in a chair exerting a force on the chair might be subject to a gravitational force, and/or an electrostatic force, and/or a magnetic one (or as John Cuthber points out, merely be accelerating). The chair itself does not have to be feeling any of those forces. It could be uncharged or made of a nonmagnetic material. We could be in a gravity-free region of space. The forces acting between two objects need not be the same as other forces acting on either of them. All we know is that if A exerts a force on B, B exerts the same kind of force on A. I think they do. There are toys where magnetic force counteracts gravity. http://s7d2.scene7.com/is/image/NationalGeographic/73097?$product320x320$ Edited September 22, 2015 by michel123456 Link to comment Share on other sites More sharing options...
Sensei Posted September 22, 2015 Share Posted September 22, 2015 Forces don't interact. Force is change of momentum in period of time. Regardless of what cause it. Electrons attract protons in matter. And repel other electrons. Like in oil drop experiment. We make oil drop positively charged by ionization caused by x-rays. Which is starting attracting to negatively charged electrode above it. And result is cancellation of gravity force in precisely measured moment. Force from electrostatic interaction, canceled force from gravitation. F=0 N overall. And oil drop is levitating inside of device. Or even flying up after increasing quantity of x-rays/voltage on plate. An object in a chair exerting a force on the chair might be subject to a gravitational force, and/or an electrostatic force, and/or a magnetic one (or as John Cuthber points out, merely be accelerating). The chair itself does not have to be feeling any of those forces. It could be uncharged or made of a nonmagnetic material. We could be in a gravity-free region of space. The forces acting between two objects need not be the same as other forces acting on either of them. All we know is that if A exerts a force on B, B exerts the same kind of force on A. This is pretty much classic physics interpretation. But let's see it from quantum physics point-of-view. Why you don't fall in chair, and into ground, to core of Earth.. ? Because electrons in chair, or ground, are repelling electrons that are in your foot. If they would be no longer existing, like when greater than Sun star collapse, and formation of neutron star, no electrons would repel your foot anymore, and you would be sucked in also. michel123456, was talking about nature of change of momentum. What is primary source. If I have photon emitted in direction of electron, like in Compton scattering experiment, and part of energy of photon is absorbed, and electron is accelerated, and new photon with less energy is made.. Particle is accelerated. Easy to calculate and measure in the real life with high voltage generator such as Van der Graaf generator. But what is gravitational equivalent of such experiment.. Obviously "produced" particle would have to have be neutral (because electron remain negatively charged regardless of height above Earth surface, and proton remain positively charged also etc.) Link to comment Share on other sites More sharing options...
swansont Posted September 22, 2015 Share Posted September 22, 2015 I think they do. There are toys where magnetic force counteracts gravity. http://s7d2.scene7.com/is/image/NationalGeographic/73097?$product320x320$ And? Do you have evidence that the magnetic force is somehow interacting with the gravitational force? Or is it as I described, that there is a gravitational force and a magnetic force separately acting on the globe? if the forces themselves were interacting (and in this case, canceling), that means in the space between the globe and the magnet, there would be no force on anything else, either. That's not what is happening. Link to comment Share on other sites More sharing options...
John Cuthber Posted September 22, 2015 Share Posted September 22, 2015 I think they do. There are toys where magnetic force counteracts gravity. http://s7d2.scene7.com/is/image/NationalGeographic/73097?$product320x320$ And there are chairs where the springyness of some cushions counteract gravity. (strictly, that's the electromagnetic force too) If you hold a Geiger counter above a radioactive source you will find that the strong and weak forces can also counter gravity and fling particles at it. So what? Link to comment Share on other sites More sharing options...
Endy0816 Posted September 22, 2015 Share Posted September 22, 2015 (edited) I think the issue stems from the fact that the energy input isn't always obvious. Easier to feel the weight of a globe held in your hand, than it is to notice a power cord snaking out from the base of a toy. Edited September 22, 2015 by Endy0816 Link to comment Share on other sites More sharing options...
John Cuthber Posted September 22, 2015 Share Posted September 22, 2015 I think the issue stems from the fact that the energy input isn't always obvious. Easier to feel the weight of a globe held in your hand, than it is to notice a power cord snaking out from the base of a toy. My chair has no power lead. Link to comment Share on other sites More sharing options...
Endy0816 Posted September 22, 2015 Share Posted September 22, 2015 Energy, not necessarily electricity. Link to comment Share on other sites More sharing options...
puppypower Posted September 22, 2015 Share Posted September 22, 2015 Gravity will often create forces that oppose gravity. For example, the rotation of a body causes an outward force. The rapidly rotating neutron star is under compression but also under tension forces, due to its rapid rotation. Another way, which interfaces the others forces is connected to the pressure generated by gravity. The pressure due to gravity causes atoms to come together closer causing a repulsion in the EM force, to generate a force opposite the direction of gravity. Neither is called anti-gravity, but both do the same thing. Another example is connected the liquid and gaseous states of matter. Lower density, like a helium balloon in air, will rise in the sky, driven by what appears to be a force opposite gravity. This force is generated by pressure, which is generated by gravity. This pressure can impact the EM forces and cause matter to change phase so it can get in motion. This is also not anti-gravity but it does the same thing in terms of force vectors. Link to comment Share on other sites More sharing options...
J.C.MacSwell Posted September 22, 2015 Share Posted September 22, 2015 I think they do. There are toys where magnetic force counteracts gravity. http://s7d2.scene7.com/is/image/NationalGeographic/73097?$product320x320$ counteract =/= interact Link to comment Share on other sites More sharing options...
swansont Posted September 22, 2015 Share Posted September 22, 2015 Energy, not necessarily electricity. A chair is not doing work. No energy, no power. Link to comment Share on other sites More sharing options...
Endy0816 Posted September 23, 2015 Share Posted September 23, 2015 There's stress involved even if the mass remains stationary. You can feel this directly by holding a decent weight out for a span of time. You manage 20 kg(~44 lbs) for all of a minute and a half and you'll have set a new record. Link to comment Share on other sites More sharing options...
Fuzzwood Posted September 23, 2015 Share Posted September 23, 2015 (edited) That's because your arm isn't a rigid body but rotates around your shoulder. You can't expect to balance a skip, sit on one end and stay in the same position either. Edited September 23, 2015 by Fuzzwood Link to comment Share on other sites More sharing options...
John Cuthber Posted September 23, 2015 Share Posted September 23, 2015 There's stress involved even if the mass remains stationary. You can feel this directly by holding a decent weight out for a span of time. You manage 20 kg(~44 lbs) for all of a minute and a half and you'll have set a new record. That's because we are not designed for that sort of thing. It's like saying that , just because you could hold it up with a fast moving jet of air- and that would take lots of power- you must use a lot of power to hold it up. A shelf can manage to hold 20 kilos "for ever" without getting tired. Energy, not necessarily electricity. My chair has no energy source. And none is needed- the "work done" is the product of the force and the distance. Since the distance moved is zero, the work done is zero. Link to comment Share on other sites More sharing options...
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