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# i was wondering about the effect of gravity on electricity, ? Answered

hypothetically, one example - would it be easier to send power from beyond the atmosphere to earth, or, send it beyond the atmosphere from earth. or another similar task whereby the scale would yeild a tangible result?

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He did in the beginning say, hypothetically... Electricity is comprised of electrons which, do in fact have mass (Appx. 1/1836 of that of a proton or neutron) therefore, gravity would influence it slightly. So slightly that it can essentially considered negligible. However, I do believe it would be infinitesimally easier to send it towards Earth. Hypothetically.

Electricity is just the flow of charges and since it doesn't have any mass,gravity has no role in determining factors for it.From your example,there's no doubt that no wires are involved when receiving signals from such distances such as 'beyond the atmosphere to earth',so obviously wireless technology is used.These signals can get interference on their journey up and down due to effluents in the atmosphere say for example clouds,especially during monsoons but no,not gravity
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i was meaning through a wire, i had not considered wireless, thanks.
i read the international space station is 400km away, maybe a wire could span that distance,

how about through a wire from the top of mount everest to the shore of the dead sea if they were side by side?

Like all others have said,gravity isn't going to have any effect on electricity even if you plan to run a wire around the whole wide world and pass electricity through it.

Nope Gravity isn't going to effect the electricity "flow"

Taking a wire up to the ISS would also be an issue.

1. The ISS isn't over the equator so it moves relative to the surface.
2. The weight of the wire would require something with more tensile strength than copper or currently understood alloys.
3. IF you could do this then putting solar panels in orbit and leading the electricity down to the ground would be a great way to solve the worlds power issues.

YES, in your case gravity will affect electricity flow.

I will explain: you say you want a cable to connect these 400 Km between ISS and earth. Well, depending on the power, a cable could weight more o less 100 g/m. that is, total 40000000 g or 40000 Tons. This facr surely will affect the orbital stability of the ISS, and consequently the electricity flow.

hmm i was reading about a 'space elevator' however ficticious, some thought has gone into exploring the idea.

now that i think of it i read a sc-fi book by isaac asimov, or arthur.c.clarke i cant remember exactly who wrote it, which spoke of a 'stairway to heaven' if you will, which was loosely based on the concept connecting space and a planet. as well as a lot of other concepts which at the time would have been considered ridiculous ie super computers, artificial intelligence, flying machines, robots androids, the list goes on.

I read that book many years ago, but the "cable" was only an atom or molecule thick, which was minimal weight.

Usually the influence of gravitational fields on the moving charges in electric circuits, or on the propagation of electromagnetic waves, is so small as to be negligible.

By the way, I think it will be helpful to consider those two cases separately: (1) electric circuits with actual charge carriers with mass (like electrons or ions), and (2) electromagnetic waves in empty space.

For the first case I think you can just use classical mechanics. For example you could ask about the influence of gravity on the electron beam in an CRT (cathode ray tube) television.
http://en.wikipedia.org/wiki/Cathode_ray_tube
How much of the beam's vertical deflection (how many millimeters at the surface of the screen) is due to gravity (i.e. to the weight of the electrons, and them "falling" through the Earth's gravitational field) ?  You could ask the same question for a beam of protons. Supposedly you'd get a lot more gravitational deflection in a beam of protons, since the mass of a proton is about 2000 times greater than that of an electron.  Still I think the deflection is going to be very small.

For the other case, regarding electromagnetic waves moving through gravitational fields, that's more tricky, since electromagnetic waves are not thought of as having actual mass, although they do carry energy, and energy kind of "looks like" mass, in a relativistic sense.
http://en.wikipedia.org/wiki/Mass%E2%80%93energy_equivalence

I have heard/read that sufficiently strong gravitational fields, like those surrounding a black hole, can actually red-shift light "climbing out" of the gravity well (or blue-shift light "falling in" to the gravity well), but I don't know how to do the calculations for that.
http://en.wikipedia.org/wiki/Relativistic_Doppler_effect

However, I am going to guess that if the classically calculated result for the escape velocity,
http://en.wikipedia.org/wiki/Escape_velocity
for some radius inside this gravity well, is much, much, less than the speed of light, then you don't have to have to worry about the (red-shifting, blue-shifting) effects due to general relativity, on electromagnetic waves moving through that gravitational field.

If I remember correctly, this was the definition of the Schwarzchild Radius:  the radius at which classically calculated escape velocity is equal to the speed of light.
i.e (2*G*M/r)^(1/2)=c  <==>  r = 2*G*M/(c^2)