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Physics : What is the speed of gravitation?
Say, we separated two masses by a distinct space. If one mass moved, how long would it take for the other mass to be effected by its gravity? Is gravitational affect constant or variable?
7 個解答
- ?Lv 73 星期前
From what I understand, the force or effect of gravity travels at the speed of light. If the sun was to suddenly blink out of existence, the Earth would continue along its orbital path for roughly 8 minutes, at which point not only would we see the light from the sun instantly stop and go dark, but then the Earth would begin to travel in a straight-line trajectory along a line tangent to where it was in its orbit.
- PhilomelLv 73 星期前
GRAVITY is a constant force, always present, in any body with mass.
The attraction between two bodies is a function of their masses and the distance between them.
F=G* (M1*M2) / D
G=6.67*10^-11.
Gravity is always present meaning it has no speed.
- ivan kLv 53 星期前
We have absolutely no clue. General Relativity is just a guess based on nothing but faith. You might as well ask a gypsy fortune teller.
What I know, is the same as what I've always known: It's in the bible stupid.
God makes gravity to hold the firmament to the disk that we call the Earth, and it propagates at the speed of God.
- Andrew SmithLv 73 星期前
We believe that it propagates at the speed of light. But imagine how to do the test. If gravity is caused by mass and we cannot create mass then how do we change the mass to determine its gravitational effects? If we could do that then how do we know WHEN the gravity is felt at the far distance? Perhaps I am wrong but I think we take it on faith and have yet to be able to make a direct test of the idea of the speed of gravity. We cannot move large bodies large distances through space to make the test you describe. Perhaps binary stars could affect other bodies nearby and the fluctuating field would give us a testable condition. Be careful of imagining that we KNOW all the answers.
- 匿名3 星期前
Effect is felt almost with zero lag (it propagates with speed = c) ; the effect changes with the squared distance (F = G*m1*m2/d^2, G being worth 6,67*10^-11 m^3/(kg*s^2)
- ?Lv 73 星期前
Gravitational causality ALWAYS travels at ‘c’ whether it be the case you describe or whether it is through gravitational waves.