# The Naked Scientists Forum

### Author Topic: LIMITED VALIDITY OF NEWTON'S LAW OF UNIVERSAL GRAVITATION  (Read 2950 times)

#### pandey_23ajay

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##### LIMITED VALIDITY OF NEWTON'S LAW OF UNIVERSAL GRAVITATION
« on: 25/04/2012 17:47:41 »
Universe consists of billions of heavenly bodies, each having different gravity, that means gravity have variable strength, now, lets say there are three planets P, Q AND R, each having gravity of  g1, g2, g3 respectively. g1>g2>g3. according to newton's law all the three 'g' should extend upto infinity and attract a mass M placed at infinity, if it is so, then strength of gravity has no meaning.
also strength of any gravity can not extend upto infinity, as gravity is force and no force can extend upto infinity.
so, gravity / attraction between two maases at infinite / large distance does not exists or is insignificant.

Result-
NEWTON'S UNIVERSAL LAW OF GRAVITATION AT LARGE / INFINITE DISTANCE IS INVALID, SO HAS LIMITED VALIDITY

#### CliffordK

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##### Re: LIMITED VALIDITY OF NEWTON'S LAW OF UNIVERSAL GRAVITATION
« Reply #1 on: 26/04/2012 00:16:15 »
Both  light from an omnidirectional source, and gravity follow the inverse square law in that intensity is proportional to the initial intensity divided by the square of the distance.

We can see stars at great distances.

In 1997, part of your night sky was illuminated by a single star going supernova (SN 1997ff) approximately 11.3 billion lightyears away.  It might not have been too impressive without a telescope, but if you were outside, a few photons might have hit you from the distant star.

So, if light travels in excess of 10 billion lightyears distance, how far does the effect of gravity reach?

Obviously the Milky Way Galaxy, about 100,000 lightyears in diameter is held together by intense interstellar gravitational forces.

Of course, you might consider significant figures.  So, while (SN 1997ff, or what is left of it) might still have a gravitational pull on Earth, it is such a tiny fraction that it could be estimated and calculated, but it would not be detectable independent from the Earth, Sun, and Milky Way.

#### pandey_23ajay

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##### Re: LIMITED VALIDITY OF NEWTON'S LAW OF UNIVERSAL GRAVITATION
« Reply #2 on: 26/04/2012 16:55:02 »
I agree with newton's law to limited distance but to very very large / infinite distance, it is insignificant.
REASON-each heavenly body have different gravity, that means gravity varies in strength, now, can each gravity, whether high strength or low, will reach upto infinity? if it reaches, then strength of gravity has no meaning and if it does not then it limits newton's law of gravitation.

if there are billion of planets and stars interacting with earth, how the balance between forces have been maintained, how is earth in such a balanced motion ? i think gravitational forces too have limit like magnetic forces and they can not extend upto infinite distance, i will give u good reason for it.
all heavenly bodies in universe have variable gravity, some have more, some less, that means gravity have varying strength, then you can not say that gravity of any strength extends upto infinity, so microgravity is only theoretical concept and not practical.
DOES TWO BODIES AT INFINITE DISTANCE ATTRACT EACH OTHER, DEFINATELY NOT BECAUSE, TO ATTRACT SOME FORCE IS REQUIRED AND NO FORCE CAN EXTEND UPTO INFINITE DISTANCE.
« Last Edit: 26/04/2012 16:59:42 by pandey_23ajay »

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##### Re: LIMITED VALIDITY OF NEWTON'S LAW OF UNIVERSAL GRAVITATION
« Reply #2 on: 26/04/2012 16:55:02 »