Naked Science Forum

Non Life Sciences => Chemistry => Topic started by: omid on 17/01/2010 17:24:33

Title: how far is the gravitational force of earth effective?
Post by: omid on 17/01/2010 17:24:33
does anyone knows about it??????? [::)]
Title: how far is the gravitational force of earth effective?
Post by: Bored chemist on 17/01/2010 18:19:14
It carries on for as far as you like, but it gets progressively weaker.
Title: how far is the gravitational force of earth effective?
Post by: omid on 18/01/2010 17:25:28
It carries on for as far as you like, but it gets progressively weaker.

Can it attract other planets towards it??????????
Title: how far is the gravitational force of earth effective?
Post by: SeanB on 18/01/2010 17:54:48
It has an effect on our neighbouring galaxies, but it is a very small effect at that distance. In essence it has an effect thoughout the visible universe, although the effect will be really hard to measure, mixed in amongst all the forces from other bodies forming the visible universe.

Title: how far is the gravitational force of earth effective?
Post by: omid on 18/01/2010 18:02:40
OK if it has, then does it effect the solar system too?????????
Title: how far is the gravitational force of earth effective?
Post by: lightarrow on 18/01/2010 19:31:33
does anyone knows about it??????? [::)]
I tell you if you tell me what does it have to do with chemistry  [:)]
Title: how far is the gravitational force of earth effective?
Post by: litespeed on 18/01/2010 19:58:23
The gravitational force of the earth extends as far as the earth has existed in years, times the distance light has traveled in that time. [This assumes the general belief gravity does not propagate instantaneously]. The strength of the force is inversely proportional to the square of the distance.

Accordingly, the direct gravitational effect of the fully developed earth extends about five billion light years in all directions. This effect operates on every particle or photon that is subject to gravitation. I am unaware of any that do not.

One big question I neither understand nor can with authority comment on is this: Is gravity in anyway subject to Red Shift. Scientists have been looking for gravity waves for years. If they ARE waves, then the question includes whether these waves have a frequency. Personally, I do not believe they are waves or have a frequency.

For instance, an atomic bomb very suddenly loses mass upon detonation. Its gravitational force is reduced accordingly. I simply believe that lesser gravitational force [accordingly dispersed with the remaining matter] simply propogates all at one time at the speed of light, just less of it. Less a wave then a bump.

PS: sean - you wrote: "In essence it has an effect thoughout the visible universe...." This is only the case if gravity is instantaneous, which I believe is not current theory. Otherwise its effect extends only about 5 billion light years.
Title: how far is the gravitational force of earth effective?
Post by: Geezer on 19/01/2010 04:28:51
The gravitational force of the earth extends as far as the earth has existed in years, times the distance light has traveled in that time. [This assumes the general belief gravity does not propagate instantaneously]. The strength of the force is inversely proportional to the square of the distance.

Accordingly, the direct gravitational effect of the fully developed earth extends about five billion light years in all directions. This effect operates on every particle or photon that is subject to gravitation. I am unaware of any that do not.

One big question I neither understand nor can with authority comment on is this: Is gravity in anyway subject to Red Shift. Scientists have been looking for gravity waves for years. If they ARE waves, then the question includes whether these waves have a frequency. Personally, I do not believe they are waves or have a frequency.

For instance, an atomic bomb very suddenly loses mass upon detonation. Its gravitational force is reduced accordingly. I simply believe that lesser gravitational force [accordingly dispersed with the remaining matter] simply propogates all at one time at the speed of light, just less of it. Less a wave then a bump.

PS: sean - you wrote: "In essence it has an effect thoughout the visible universe...." This is only the case if gravity is instantaneous, which I believe is not current theory. Otherwise its effect extends only about 5 billion light years.

Hang on a minute. Surely the matter that currently comprises the Earth predates the existence of the Earth as an actual planet? That matter must also have produced a gravitational field long before the existence of this planet. So, would the field not extend much further into space than five billion light years?

Mind you, I'm with Lightarrow. What does this have to do with Chemistry?
Title: how far is the gravitational force of earth effective?
Post by: flr on 18/02/2010 19:18:52

 They extend as far as light from Earth traveled since Earth was formed (5 billions years ago). Note that the space further expanded during this time and hence pushed "further than 5 billions light-years distance" the "first photon reflected from Earth".