Gravitational field of earth

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Jack

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Re: Gravitational field of earth
« Reply #30 on: August 24, 2008, 06:56:57 AM »
Yes, he requires to calculate something with formula which isn't meant to calculate it. Formula quite simply states that two masses are needed. And photon doesn't have mass as he itself says. It's like I give you the only one object and require you to calculate gravitational attraction between this one object and nothing. So, no I don't get the point.
(sigh) I'll make this simple: he is basically trying to say the formula is incomplete. You seem to be having a hard time inferring his point.

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zork

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Re: Gravitational field of earth
« Reply #31 on: August 24, 2008, 08:52:53 AM »
(sigh) I'll make this simple: he is basically trying to say the formula is incomplete. You seem to be having a hard time inferring his point.
(sigh) Point is, formula is for one thing and it works for it. What the use is saying that formula doesn't do what I want when I don't give it all parameters or when I put it in situation which isn't correct for it. You don't use quite same physical formulas on normal events and on quantum events or when scales are universe versus atoms and electrons. So yes, you can say I have hard time getting to the point.
Rowbotham had bad eyesight
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http://thulescientific.com/Lynch%20Curvature%202008.pdf - Visually discerning the curvature of the Earth
http://thulescientific.com/TurbulentShipWakes_Lynch_AO_2005.pdf - Turbulent ship wakes:further evidence that the Earth is round.

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divito the truthist

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Re: Gravitational field of earth
« Reply #32 on: August 24, 2008, 09:01:00 AM »
zork, are you being obtuse on purpose?
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zork

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Re: Gravitational field of earth
« Reply #33 on: August 24, 2008, 09:17:07 AM »
zork, are you being obtuse on purpose?
No, I just live on round earth and have a hard time to get to the point presented by people living on flat earth.
Rowbotham had bad eyesight
-
http://thulescientific.com/Lynch%20Curvature%202008.pdf - Visually discerning the curvature of the Earth
http://thulescientific.com/TurbulentShipWakes_Lynch_AO_2005.pdf - Turbulent ship wakes:further evidence that the Earth is round.

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divito the truthist

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Re: Gravitational field of earth
« Reply #34 on: August 24, 2008, 09:24:21 AM »
You think you live on a spherical Earth. Anyways, the point of Robbyj's post is to showcase the insufficiency, and in blatant terms, incorrectness of Newton's version of gravitation.
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cbreiling

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Re: Gravitational field of earth
« Reply #35 on: August 24, 2008, 11:35:26 AM »
This is a great example of the obfuscation by introducing the red herring:

First Clydeaferret gives the law of universal gravitation:
According to the law of universal gravitation, the attractive force (F) between two bodies is proportional to the product of their masses (m1 and m2), and inversely proportional to the square of the distance (r) between them:

    F = G \frac{m_1 m_2}{r^2}.

Then Robbyj whips out the red herring:
Ok, now use your equation to calculate the force between the sun and a photon.

Yeah, talking about photons is a great way of ignoring the usefulness of the law of universal gravitation.  ::)

A few posts later:
No, he is proving that the Newtonian equation becomes invalid in explaining the world events, due to its inconsistency with some phenomenons. For example, gravitational lensing.

This is great. Gravitational Lensing is now a "world event" making Newtonian equations invalid. Did anyone pick up on the fact that the title of this thread is "the gravitational field of Earth"? Some posters here are carrying the FET torch that Newtonian equations are invalid because they break down under extreme circumstances which don't routinely occur on Earth or in our solar system.

If the debaters stuck to purely solar system mechanics (or as the OP intended, gravitational field of Earth), then there really isn't a whole lot to talk about with regards to whether gravity affects photons, as happens in gravitational lensing.
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Jack

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Re: Gravitational field of earth
« Reply #36 on: August 24, 2008, 11:42:56 AM »
Quote
Yeah, talking about photons is a great way of ignoring the usefulness of the law of universal gravitation.
That's the whole point.

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Roundy the Truthinessist

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Re: Gravitational field of earth
« Reply #37 on: August 25, 2008, 12:33:34 PM »
This is a great example of the obfuscation by introducing the red herring:

First Clydeaferret gives the law of universal gravitation:
According to the law of universal gravitation, the attractive force (F) between two bodies is proportional to the product of their masses (m1 and m2), and inversely proportional to the square of the distance (r) between them:

    F = G \frac{m_1 m_2}{r^2}.

Then Robbyj whips out the red herring:
Ok, now use your equation to calculate the force between the sun and a photon.

Yeah, talking about photons is a great way of ignoring the usefulness of the law of universal gravitation.  ::)

Okay, nobody here disputes the usefulness of Newton's laws of gravity.  We are only disputing his correctness.  He was wrong about there being a force.  He was wrong about gravity, whether the equations work in most cases or not; it only takes one example where they don't work out to prove that they are fundamentally wrong.

But nobody disputes that his equations can be useful.  Please quit with the straw men.  ::)
Where did you educate the biology, in toulet?

Re: Gravitational field of earth
« Reply #38 on: August 25, 2008, 01:12:59 PM »
This is a good question. I personally feel a FE model with a rotating earth exhibiting gravitation is more likely, but I'd be interested to hear the opinions of those FEers who think the Earth does not have a gravitational field.

How fast do you think the earth is rotating? Relative to the solarearthsystem.
Ooompa ooompa

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cbreiling

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Re: Gravitational field of earth
« Reply #39 on: August 25, 2008, 08:57:00 PM »
Okay, nobody here disputes the usefulness of Newton's laws of gravity.
Excuuuuuze me?  :) Newton's law of gravity is the most heavily-slandered piece of science here on the Flat Earth Forums. Mostly it takes the form of "gravity doesn't exist." Frequently anyone who dares suggest that behaviors of objects in Earth's gravitation can be perfectly described by F=Gm1m2/r2 is promptly pilloried because "Gravity isn't a force," and because objects fall towards Earth with an acceleration of 9.8 m/s/s because the Earth and Universe are doing the UA zoom "to infinity... and beyond!"

I'd say this counts as "disputing the usefulness of Newton's laws."

I know perfectly well that Einstein's equations are necessary for calculating high-energy stuff like black holes and gravitational lensing, yadda yadda, but you can't beat an algebra equation for describing routine real-world phenomena like trajectories and bouncing balls, versus the tensor calculus needed for Einstein's stuff.

From the University of New South Wales in Sydney, comes this discussion of the limitations of Newton:
Quote
Although [Newton's theory of Universal Gravitation] is an excellent theory, it does not agree with experiment if one investigates extremely large fields, or moderately large fields with very high precision. In other words, it is wrong. However, it is such an excellent approximation that Newtonian gravity is what we use to calculate in almost all circumstances, while recognising that it is just a very convenient approximation to more exact theories.

There's a good reason why every gravity problem in an engineering textbook can be correctly solved using algebra (plus trig and calculus), even if using by Einstein's formulas and tensors you'll get the same answers, to a very high degree of precision. That reason is that Newton's equations are useful, even if they've been eclipsed by more-accurate ones from Einstein.

We are only disputing his correctness.

You conveniently forget that several planets were discovered mathematically using Newton's equations. When you write of "disputing correctness" exactly how many digits of precision do you want when calculating things here on earth, like the apparent force of gravity exerted by a Zetetic Armchair? Why don't Flat Earthers propose dropping the "Universal" from the name Newton's Law of Universal Gravitation? The formula still works for 99% of real-world applications outside high-energy physics.

But nobody disputes that his equations can be useful. Please quit with the straw men.  ::)

 ??? Name the author of the quote: "He was wrong about there being a force. He was wrong about gravity, whether the equations work in most cases or not; it only takes one example where they don't work out to prove that they are fundamentally wrong." That was none other than Roundy the Truthinessist!  :P "Nobody disputes" indeed!

Dude, you need some glasses.  :) Almost every Flat Earther on these boards disputes the usefulness of Newton's equations, simply because then they'd have to admit that the entire Flat Earth must have no mass.

Boo-yah.
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It's because you asked about data. Theories can be pulled from the rectum without any apparent embarrassment, but pulling data from there is embarrassing even here. lol

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Roundy the Truthinessist

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Re: Gravitational field of earth
« Reply #40 on: August 25, 2008, 08:59:04 PM »
You're just wrong about this, and I think you completely misunderstood what I was saying.  Newton was wrong about gravity, however useful his equations might be.  Sorry you can't grasp that concept.
Where did you educate the biology, in toulet?

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cbreiling

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Re: Gravitational field of earth
« Reply #41 on: August 25, 2008, 09:15:16 PM »
You're just wrong about this, and I think you completely misunderstood what I was saying.  Newton was wrong about gravity, however useful his equations might be.  Sorry you can't grasp that concept.

You could claim "humans are wrong about breathing" (you know that universal law where it says you breathe in, breathe out, and you stay alive).

It works 99.9% of the time, but it doesn't work underwater or in a smoke-filled room (unless it's ganja), so I propose that everyone here who thinKs "breathing is fundamentally wrong" should stop immediately.

Do I have to tell you esteemed dudes fifty freaking times that I know that there is no force of gravity, it's all just space-time bendy geodesics? I get it already! I'm still sticking with Newton, and I still believe the Earth has mass.  :P

Having said all that, sorry if I misunderstood your meaning.
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It's because you asked about data. Theories can be pulled from the rectum without any apparent embarrassment, but pulling data from there is embarrassing even here. lol

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Parsifal

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Re: Gravitational field of earth
« Reply #42 on: August 25, 2008, 10:06:47 PM »
How fast do you think the earth is rotating?

Rotation is not a relative concept, and the Earth is rotating once every 23 minutes 56 seconds, or with an angular velocity of 7.3 * 10-5 s-1.
I'm going to side with the white supremacists.

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cbreiling

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Re: Gravitational field of earth
« Reply #43 on: August 25, 2008, 11:12:52 PM »
...angular velocity of 7.3 * 10-5 s-1.

Watch those units, Steve. You used "hertz" above.  :) (Lame attempt at busting chops.)
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It's because you asked about data. Theories can be pulled from the rectum without any apparent embarrassment, but pulling data from there is embarrassing even here. lol

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Parsifal

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Re: Gravitational field of earth
« Reply #44 on: August 25, 2008, 11:14:42 PM »
...angular velocity of 7.3 * 10-5 s-1.

Watch those units, Steve. You used "hertz" above.  :) (Lame attempt at busting chops.)

That is the correct unit for angular velocity.
I'm going to side with the white supremacists.

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Jack

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Re: Gravitational field of earth
« Reply #45 on: August 25, 2008, 11:35:32 PM »
It works 99.9% of the time
Keep posting this number; it just shows how unsophisticated you are.

Re: Gravitational field of earth
« Reply #46 on: August 26, 2008, 12:40:42 AM »
Rotation is not a relative concept, and the Earth is rotating once every 23 minutes 56 seconds, or with an angular velocity of 7.3 * 10-5 s-1.

That is sweet. What about the centripetal force? The FE radius and speed must give a lot of that force near the edges.

I see two paths.
The first one is that the rotation itself causes "gravity", that somehow cancels out the centripetal force.

The second one is that earth is concave. That explains why water isnt dragged out to the edges. And why youre not "pulled" straight down with "gravity", but also sideways, making it feel that earth is tilting. 

I like the earth being concave (CE! hehe). But it means that light has to be even more bent than on FE.

Im not trying to prove anything, just want to excerice those lazy grays.
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Parsifal

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Re: Gravitational field of earth
« Reply #47 on: August 26, 2008, 02:09:36 AM »
That is sweet. What about the centripetal force? The FE radius and speed must give a lot of that force near the edges.

I see two paths.
The first one is that the rotation itself causes "gravity", that somehow cancels out the centripetal force.

The second one is that earth is concave. That explains why water isnt dragged out to the edges. And why youre not "pulled" straight down with "gravity", but also sideways, making it feel that earth is tilting. 

I like the earth being concave (CE! hehe). But it means that light has to be even more bent than on FE.

Im not trying to prove anything, just want to excerice those lazy grays.

It is my view that the Earth's gravitation cancels out the centripetal force.
I'm going to side with the white supremacists.

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divito the truthist

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Re: Gravitational field of earth
« Reply #48 on: August 26, 2008, 04:35:27 AM »
You could claim "humans are wrong about breathing" (you know that universal law where it says you breathe in, breathe out, and you stay alive).

It works 99.9% of the time, but it doesn't work underwater or in a smoke-filled room (unless it's ganja), so I propose that everyone here who thinKs "breathing is fundamentally wrong" should stop immediately.

If you had actually read what Roundy posted, he never said that we can't use Newton's equations, but that for some things (like breathing) it doesn't work.
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Dr Matrix

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Re: Gravitational field of earth
« Reply #49 on: August 26, 2008, 04:41:46 AM »
If the centripetal force were cancelled by the Earth's gravitation then wouldn't that require a gradual changing of Fg (where I set this to be the vector describing the force due to gravitation) such that the angle it meets the surface changes uniformly with latitude from the North Pole to the Ice Wall? Such an explanation would require a peculiar distribution of mass in the FE and would not prevent the FE from collapsing into a sphere under its own gravitation.

There are other rotation-based issues with FE as well which are not fixed by a rotating plane/disc, such as relativistic frame dragging and the geodetic effect - the results of experiments measuring these phenomena would disagree with predictions made for a rotating sphere. Additionally, a rotating FE does not explain the lower value of g (as in, the observed acceleration due to gravitation) at the equator, which in RE is due to the centrifugal pseudo-force.  Does FE have any explanation for these phenomena?
Quote from: Arthur Schopenhauer
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Re: Gravitational field of earth
« Reply #50 on: August 26, 2008, 10:56:46 AM »
It is my view that the Earth's gravitation cancels out the centripetal force.

Is there a model from that theory around here somewhere?
Otherwise it would be cool if someone created one. Using the proposed centripetal force as basis (?).
Ooompa ooompa

Re: Gravitational field of earth
« Reply #51 on: August 26, 2008, 03:00:58 PM »
Why are we arguing about gravity?  It seems that the Flat Earthers want us to prove that gravity exists in order to prove that the Earth is a sphere.  Gravity is a phenomena which we all experience our whole lives, but has properties which physicists have difficulty explaining.  I’m sure that some of you have seen the PBS shows on modern physics which describes some of these issues.  There are also several very good books that you can read.  Just Google search “Modern Physics”.  My point is, why do we have to prove anything about gravity in order to prove that the earth is a sphere?  We don’t.  We have pictures from space.  We have satellites which orbit around the earth.  Your claim that the earth is flat is so ridiculous that I don’t really think that you are being serious.

Re: Gravitational field of earth
« Reply #52 on: August 26, 2008, 03:04:06 PM »
Why are we arguing about gravity?  It seems that the Flat Earthers want us to prove that gravity exists in order to prove that the Earth is a sphere.  Gravity is a phenomena which we all experience our whole lives, but has properties which physicists have difficulty explaining.  I’m sure that some of you have seen the PBS shows on modern physics which describes some of these issues.  There are also several very good books that you can read.  Just Google search “Modern Physics”.  My point is, why do we have to prove anything about gravity in order to prove that the earth is a sphere?  We don’t.  We have pictures from space.  We have satellites which orbit around the earth.  Your claim that the earth is flat is so ridiculous that I don’t really think that you are being serious.

Gravity doesnt exist, duh  ::)

Re: Gravitational field of earth
« Reply #53 on: August 26, 2008, 03:06:15 PM »
Why are we arguing about gravity?  It seems that the Flat Earthers want us to prove that gravity exists in order to prove that the Earth is a sphere.  Gravity is a phenomena which we all experience our whole lives, but has properties which physicists have difficulty explaining.  I’m sure that some of you have seen the PBS shows on modern physics which describes some of these issues.  There are also several very good books that you can read.  Just Google search “Modern Physics”.  My point is, why do we have to prove anything about gravity in order to prove that the earth is a sphere?  We don’t.  We have pictures from space.  We have satellites which orbit around the earth.  Your claim that the earth is flat is so ridiculous that I don’t really think that you are being serious.
I'm sure if you stick around long enough, someone will show you that cheese is proof that the earth is flat.  ;D
Stick around - it's funny

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cbreiling

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Re: Gravitational field of earth
« Reply #54 on: August 26, 2008, 05:29:58 PM »
...angular velocity of 7.3 * 10-5 s-1.

Watch those units, Steve. You used "hertz" above.  :) (Lame attempt at busting chops.)

That is the correct unit for angular velocity.

Dude, you're supposed to be the physics student! The units of angular velocity are "degrees per second" not "per second" (hertz) as you wrote.  :)

It works 99.9% of the time
Keep posting this number; it just shows how unsophisticated you are.

Sorry Marshal, I meant to write 99.89372. That's much more sophisticated.  :P

As for gravity / gravitation / motion along geodesics... What's the mass of the Earth in FET? (I'm honestly curious, and it's not meant as a rhetorical question.)

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It's because you asked about data. Theories can be pulled from the rectum without any apparent embarrassment, but pulling data from there is embarrassing even here. lol

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Parsifal

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Re: Gravitational field of earth
« Reply #55 on: August 26, 2008, 08:13:20 PM »
...angular velocity of 7.3 * 10-5 s-1.

Watch those units, Steve. You used "hertz" above.  :) (Lame attempt at busting chops.)

That is the correct unit for angular velocity.

Dude, you're supposed to be the physics student! The units of angular velocity are "degrees per second" not "per second" (hertz) as you wrote.  :)

I am a physics student, yes. That is how I know that I used the correct unit for angular velocity.
I'm going to side with the white supremacists.

Re: Gravitational field of earth
« Reply #56 on: August 27, 2008, 05:50:40 AM »
...angular velocity of 7.3 * 10-5 s-1.

Watch those units, Steve. You used "hertz" above.  :) (Lame attempt at busting chops.)

That is the correct unit for angular velocity.

Dude, you're supposed to be the physics student! The units of angular velocity are "degrees per second" not "per second" (hertz) as you wrote.  :)

I am a physics student, yes. That is how I know that I used the correct unit for angular velocity.

The SI unit is radians per second (http://en.wikipedia.org/wiki/Radians_per_second), but can also be converted to other units such as Hz, where 1 rad/s = 1/2π Hz

Moving swiftly along...
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A Budget of Paradoxes - A. de Morgan (pp 306-310)

Re: Gravitational field of earth
« Reply #57 on: August 27, 2008, 07:20:55 AM »
That is sweet. What about the centripetal force? The FE radius and speed must give a lot of that force near the edges.

I see two paths.
The first one is that the rotation itself causes "gravity", that somehow cancels out the centripetal force.

The second one is that earth is concave. That explains why water isnt dragged out to the edges. And why youre not "pulled" straight down with "gravity", but also sideways, making it feel that earth is tilting. 

I like the earth being concave (CE! hehe). But it means that light has to be even more bent than on FE.

Im not trying to prove anything, just want to excerice those lazy grays.

It is my view that the Earth's gravitation cancels out the centripetal force.

Can you please explain how?  I'm trying to picture this in my mind's eye...the gravitation effect is pulling us essentially straight down towards the earth, but wouldn't the centripetal force of the rotating earth be at 90 degrees to the gravitational force?  I'm not sure I understand how this could cancel out...in order or that to work out, wouldn't the forces need to be 180 out of phase like noise cancelling headphone use counternoise sinewaves to cancel out noice sine waves?

This is the first time I've noticed any FE indication that the earth is rotating...usually the models presented have the spotlight-sun moving in some sort of ellipse above the surface of the earth...any rotation brings into play a force that works at a right angle to the gravitational effect we feel (or the continuous acceleration that our minds perceive as gravitation).  I'm genuinely curious about any information and/or explanation that you may put forth.

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Dr Matrix

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Re: Gravitational field of earth
« Reply #58 on: August 27, 2008, 07:45:41 AM »
If the centripetal force were cancelled by the Earth's gravitation then wouldn't that require a gradual changing of Fg (where I set this to be the vector describing the force due to gravitation) such that the angle it meets the surface changes uniformly with latitude from the North Pole to the Ice Wall? Such an explanation would require a peculiar distribution of mass in the FE and would not prevent the FE from collapsing into a sphere under its own gravitation.

There are other rotation-based issues with FE as well which are not fixed by a rotating plane/disc, such as relativistic frame dragging and the geodetic effect - the results of experiments measuring these phenomena would disagree with predictions made for a rotating sphere. Additionally, a rotating FE does not explain the lower value of g (as in, the observed acceleration due to gravitation) at the equator, which in RE is due to the centrifugal pseudo-force.  Does FE have any explanation for these phenomena?
Quote from: Arthur Schopenhauer
All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident.

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Jack

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Re: Gravitational field of earth
« Reply #59 on: August 27, 2008, 07:46:49 AM »
Sorry Marshal, I meant to write 99.89372. That's much more sophisticated.  :P
Right, so how did you get this number?