# The Naked Scientists Forum

### Author Topic: What is the accepted value of g?  (Read 7056 times)

#### jeffreyH

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##### Re: What is the accepted value of g?
« Reply #25 on: 27/03/2014 02:45:06 »
You might try this.. http://www.scientificamerican.com/article/puzzling-measurement-of-big-g-gravitational-constant-ignites-debate-slide-show/

If you look at the CODATA value in that article it is 6.67384(80) X 10-11 m3 kg-1 s-2. My calculation in the second post here http://www.thenakedscientists.com/forum/index.php?topic=50733.0 is 6.673837e-11 using the equation with g = 1 and r = 1. I think the CODATA and this calculation being equal says quite a lot.
« Last Edit: 09/04/2014 12:32:48 by jeffreyH »

#### Bored chemist

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##### Re: What is the accepted value of g?
« Reply #26 on: 27/03/2014 20:43:52 »
"The gravitational field of the earth will always have an effect on the attraction of two bodies within its field. The pull towards the centre of the earth will change the momentum between the two masses being measured. You also have complex cancellation effects to take into account."

Or,  to counter the effect of Earth's gravity, you could hang them from bits of string like Mr Cavendish did.

Also, you need to show how you "calculated" G before anyone can make any meaningful comment on it.
My guess is that you have used a circular argument.
« Last Edit: 27/03/2014 20:49:10 by Bored chemist »

#### jeffreyH

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##### Re: What is the accepted value of g?
« Reply #27 on: 27/03/2014 22:53:10 »
"The gravitational field of the earth will always have an effect on the attraction of two bodies within its field. The pull towards the centre of the earth will change the momentum between the two masses being measured. You also have complex cancellation effects to take into account."

Or,  to counter the effect of Earth's gravity, you could hang them from bits of string like Mr Cavendish did.

Also, you need to show how you "calculated" G before anyone can make any meaningful comment on it.
My guess is that you have used a circular argument.

You do need to understand that the Planck length relies upon G and so is a bad choice in any equation as that is circular. I will post the method shortly.

#### Bored chemist

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##### Re: What is the accepted value of g?
« Reply #28 on: 29/03/2014 20:36:59 »
I'm pretty sure you are using a circular argument.
The planck length is calculated from the value of G so you can't use it to calculate G.

#### JP

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##### Re: What is the accepted value of g?
« Reply #29 on: 02/04/2014 14:52:13 »
While we appreciate the points you're raising about the difficulty of measuring G, if you're going to propose your own theory on the matter, please keep it to New Theories.  This forum is meant to answer questions in terms of mainstream physics, not to promote new theories.

Thanks!

-the mods

#### jeffreyH

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##### Re: What is the accepted value of g?
« Reply #30 on: 02/04/2014 18:41:52 »
While we appreciate the points you're raising about the difficulty of measuring G, if you're going to propose your own theory on the matter, please keep it to New Theories.  This forum is meant to answer questions in terms of mainstream physics, not to promote new theories.

Thanks!

-the mods

My apologies. I got a little carried away.

#### The Naked Scientists Forum

##### Re: What is the accepted value of g?
« Reply #30 on: 02/04/2014 18:41:52 »