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#43931 - 06/07/12 04:42 PM Re: Earths Water in a Ball [Re: Orac]
paul Offline
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Orac

its obvious that greenlands glaciers are not even a tiny fraction of the total weight of the ice on top of greenland
wouldnt you say?

so why are you using greenlands glaciers when talking about the rebounding of the entire greenland landmass.

Quote:
The initial uplift following deglaciation was near-instantaneous due to the elastic response of the crust as the ice load was removed.


deglaciation --> as the ice load was removed

near-instantaneous due to the elastic response of the crust

even your example of glaciers show a near-instantaneous elastic response of the crust.

granted that responce would be small , nothing to really get concerned with.

but the rebounding of a continent would be something to really be concerned with.

lets hope it all goes smoothly and the solid rock beneath the continents are actually very elastic like rubber and there will be no devastation due to the cracking of the crust.

lets also hope that we win the lottery.


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#43932 - 06/07/12 04:50 PM Re: Earths Water in a Ball [Re: paul]
Orac Offline
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Basic physics pressure is per square area.

Changing the area doesn't change the problem divid the mass by the volume it sits on. If you are saying the thickness on the glaciers is thinner per square meter than the mainland then maybee it's not an indicator.

To explain above you let air out of car tyres to drive on beaches so the tyre spreads out the load and it doesn't sink into the sand very similar problem to what you are looking at. Weight per area is the key thing not total weight.

Again I am no expert on geology I am simply applying simple physics principles and what I would have natively guessed should happen wiki says does.

There may be mechanisms I do not undertsand if so explain away.

To me this is like a classic ice block problem when put out on table initially the melt rate increases but eventually it slows down and declines because you start running out of surface area on the iceblock to keep up the melt rate increase. The more the iceblock melts and smaller it becomes the less surface area it has.

So taking that to greenland what i would expect happen if what you suggest happened the melt rate would initially increase then level and decrease and the instantaneous glacial rebound should do the same.


Edited by Orac (06/07/12 04:59 PM)
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#43933 - 06/07/12 05:06 PM Re: Earths Water in a Ball [Re: Orac]
paul Offline
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Quote:
Changing the area doesn't change the problem divid the mass by the volume it sits on. If you are saying the thickness on the glaciers is thinner per square meter than the mainland then maybee it's not an indicator.


no...

think about it this way.

you have a 50 ft x 50 ft x 10 ft deep swimming pool sitting on a weight scale.

the water in the pool weighs 1,559,520 pounds.

you have a water hose leading from the pool to the ground.

you are using the water hose to siphon off water from the pool.

the pool of water is greenland.
the water hose is a greenland glacier.


the weight scale is sitting on a huge spring and the spring is compressed due to the weight of the water in the pool.

will the weight that the scale shows be greatly affected
if you remove the water hose?

will the compressed spring be greatly affected by removing the water hose?

will a glacier melting greatly affect the rebounding of greenland?
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#43934 - 06/07/12 05:59 PM Re: Earths Water in a Ball [Re: paul]
Orac Offline
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Again totally wrong way of looking at it.

There is an exact equivalent in how much weight can an egg shell support that is identical in all respects to our issue with weight on earth crust.

Answer a hell of a lot if if you spread the load out

http://www.stevespanglerscience.com/experiment/walking-on-eggshells

http://www.sciencefairadventure.com/ProjectDetail.aspx?ProjectID=176

The deformation of the egg shell per unit area decides whether it breaks or not the total weight sitting on the egg.

I assure you that is the exact same situation and weight per unit area matters on earth not the weight itself.

There are no springs involved you have a thin crust which is being deformed based on the pressure per area on it. The crust will flex in the same way as the eggshell does based on that pressure and so long as the pressure isnt on a singular point it will tolerate alot.

It's also why semi trailers have multiple wheels to keep the weight spread out so the wheels don't sink into and crack the tarmac.

If you still aren't convinced get a party ballon and blow it up. Put a finger tip from each hand on either side and push and note the deflection you should be able to touch finger tips if it is moderately inflated. Now use the flats of your hands and try and get the walls to move anywhere near as close .... Area matters :-)


Edited by Orac (06/07/12 06:33 PM)
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#43935 - 06/07/12 08:03 PM Re: Earths Water in a Ball [Re: Orac]
paul Offline
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Quote:
There is an exact equivalent in how much weight can an egg shell support


Come on Orac you shouldnt use an egg shell when making an example of the earth , however your use of a balloon was a good example.

that is about as wrong as you could get , I could see if you were to use a egg whose shell has been cracked several times and the cracks were all connected.

as in the below egg shell whose cracks are all connected!



do you think that this egg shell would support that much weight?



extremely wrong Orac ;-)

ie...

the earth has cracks in it , as below in much the same manner as the cracked egg shell above does.



find a mirror look into it at yourself and say this.

Quote:
Again totally wrong way of looking at it.



Quote:
I assure you that is the exact same situation and weight per unit area matters on earth not the weight itself.


get a really thin sheet of cardboard.
apx 1/8 inch x 12 inch x 12 inch
fill you bathtub with water.
place the sheet of cardboard on top of the water.

now go to mcdonnalds and get a large coke.

slowly take ice from your drink and place the ice on the thin sheet of cardboard. (starting at the center of the thin sheet of cardboard)

notice how the cardboard begins to sink into the water.

now take a picture of it.

then wait until the ice melts.

take another picture of it.

compare the differences in height above water level.


repeat the experiment only this time cut the cardboard into
squares.
make (9) 4 inch x 4 inch squares.

place the small squares in the water in your bathtub.
assemble the small squares into a large square

note : do not use superglue, nails, cement or any other means to reconnect the squares together in order to sabotage the experiment just to prove your point.

when you place the ice on the center 4 x 4 inch square
does the center square sink more rapidly than the 12 x 12 square used in the previous experiment?

can it hold as much ice as the 12 x 12 square used in the previous experiment?

knowing that water is not as thick as magma is you should repeat the experiment using strawberry pudding.

will the strawberry pudding support the ice sitting on top of the center square better than the water?

if not do you think it would be better to pour concrete into your bathtub to use as the supportive structure that the earths crust sit on?

do you think it would be even better if you allow the concrete to fully dry before performing the experiment?


is there any way out of this?

Quote:
Now use the flats of your hands and try and get the walls to move anywhere near as close .... Area matters :-)


yes it does.

and applying an example correctly also matters.

hers a good one.

place your balloon between two surfaces then put your fingers on the top and bottom of the balloon.

press your fingers into the balloon until the balloon touches the two surfaces in a manner that the periphery (equator) of the balloon is touching the two surfaces.

now consider the fingers as the ice caps.
as long as you hold pressure on the balloons north and south poles the balloons periphery will support the balloon because it is in contact with the two surfaces.

as soon as you release pressure from the poles the balloon will drop.

the pressure is distributed evenly inside the balloon.

so... why didnt the 4 x 4 inch square support as much ice as the 12 x 12 inch square.

would this mean that the areas further away from the poles will not be as affected as those areas closer to the poles?

when you moved your fingers didnt the balloon regain its original shape?










_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#43936 - 06/08/12 02:16 AM Re: Earths Water in a Ball [Re: paul]
Orac Offline
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You are getting close to understanding now keep playing with the idea ... In physics it's a standard closed vessel under pressure problem.

To turn your problem to closer to reality take your cracked egg world put on the ground now get a fixed block weight and now get different cup sizes. Turn the cup upside down and place cup on your cracked world now put your standard weight ontop of the upturned base. The different cup sizes are spreading the load of the standard weight out over different areas, note the movement distances in your cracked egg shell.

As I said I am sure at what is happening I would have guessed at it. Note also that the direction is a lift it is working against sea level rise.

Infact there is a logical extension if the physics is working as I describe .... If all the ice on antarctica melted the one place I can >>> guarantee <<< you that won't be under water is antarctica.

Similarly at the moment sea levels around greenand should actually be dropping ....and the answer

Originally Posted By: http://www.cicero.uio.no/fulltext/index.aspx?id=8912

In other words, the paradoxical result will be that as the Greenland ice melts, world sea level will rise because more water enters the oceans, but the sea level around Greenland itself will drop because the island loses mass and its gravity is weakened. The map shows the expected pattern of sea level rise around the world if melting of the Greenland Ice Sheet results in an average sea level rise of one millimetre per year, or 10 centimetres in 100 years. We can see that there will be no sea level rise at all around Greenland – in fact, the sea level will sink, but this is not apparent from the simplified map.


What is described as paradoxical is infact completely obvious if you understand what is happening.

Seriously it's basic physics ... you keep telling me I am wrong but my predictions keep showing otherwise.


Edited by Orac (06/08/12 02:35 AM)
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#43937 - 06/08/12 03:32 AM Re: Earths Water in a Ball [Re: Orac]
paul Offline
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Registered: 03/21/06
Posts: 4135
Quote:
To turn your problem to closer to reality take your cracked egg world put on the ground now get a fixed block weight and now get different cup sizes. Turn the cup upside down and place cup on your cracked world now put your standard weight ontop of the upturned base. The different cup sizes are spreading the load of the standard weight out over different areas, note the movement distances in your cracked egg shell.


shazam I would never have figured that one out.
now I fully understand.



Quote:
You are getting close to understanding now keep playing with the idea ... In physics it's a standard closed vessel under pressure problem.


Im so glad that you are here to explain these things
just think we have nothing to worry about because the sea levels will only rise a couple of millimeters per hundred years.

unless we live on greenland or the antartic which will be the safest places on the earth to live because the sea levels will drop there , wow


Quote:
Greenland itself will drop because the island loses mass and its gravity is weakened.

so all we have to do to weaken gravity is melt ice.
I feel as if I have been left out , I always thought that gravity was constant on the earth and did not change like that.

thanks Orac for letting me in on that secret.





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#43938 - 06/08/12 04:20 AM Re: Earths Water in a Ball [Re: paul]
Orac Offline
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Loc: Currently Illinois, USA
Originally Posted By: paul

Im so glad that you are here to explain these things
just think we have nothing to worry about because the sea levels will only rise a couple of millimeters per hundred years.


The sea level is moving at 3.2mm per year estimate because it is made up of multiple sources try looking at the breakdown of contributions before making stupid statements.

Originally Posted By: http://www.realclimate.org/index.php/archives/2007/03/the-ipcc-sea-level-numbers/

Greenland has contributed +0.14 to +0.28 mm/year of sea level rise over this period, while for Antarctica the uncertainty range is -0.14 to +0.55 mm/year.


Hmmmm greenland contributes max of 0.28mm to sea level and the island is lifting 0.6mm per year ... hmmm I wonder why, does your theory cover that.

Originally Posted By: paul

unless we live on greenland or the antartic which will be the safest places on the earth to live because the sea levels will drop there , wow


Antarctica can never go under water this is not enough water not already in the ocean on the planet to do that.

Antarctica has the greatest average elevation of any continent at 1,860 metres (6,100 feet). The average elevation of North America is 720 metres (2,300 feet).

That is before including the uplift of the continent if all the ice melted.

Greenland could go under because of the contribution of ice melt from antarctica and other sources into the ocean.


Originally Posted By: paul

so all we have to do to weaken gravity is melt ice.
I feel as if I have been left out , I always thought that gravity was constant on the earth and did not change like that.


Then you would be stupidly wrong gravity is not constant and thats exactly how GRACE works out changes. There are micro gravity changes around you all the time that you are blissfully unaware of. GRACE measures ice melt by monitoring the gravity changes (http://www.jpl.nasa.gov/news/news.cfm?release=2012-036) so are you suggesting GRACE doesn't work and is wrong?

http://www.space.com/11849-earth-gravity-map-geoid.html




Grace even sees Earthquakes because they change gravity here is the 2004 sumatra quake



I am sorry that the actual science of gravity messes with your actual perception and you find it gibberish but it none the less accurate to a scientist.


Edited by Orac (06/08/12 04:51 AM)
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#43941 - 06/08/12 11:45 AM Re: Earths Water in a Ball [Re: Orac]
paul Offline
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Posts: 4135
I suppose that the old gravity constant has been done away with
by grace.

unless the changes in gravity that grace detects are so tiny
that they really have no affect on the amount of gravity in
areas that grace detects differences.

could it be that these micro changes dont really affect the
actual weight of objects to any great extent and these miniscule micro changes in gravity can only be detected on sensitive measuring equipment?

and these really tiny miniscule micro changes in gravity are not what causes sea levels to decline.

the information that you posted seems to tell us that it is not the weight of the ice melting but a decrease in greenlands gravity that causes sea levels around greenland to sink as the information says.

since you are a scientist could you please inform us what the new gravity constant is when grace is around.

I dont want to be measuring anything valuable at the wrong time
or should I say when the gravity of the situation is declining.

maybe we wont all be trapped by these tiny miniscule micro atom sized barely detectable changes and fall up into the air.



_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#43942 - 06/08/12 12:40 PM Re: Earths Water in a Ball [Re: Mike Kremer]
Bill S. Offline
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Registered: 08/20/10
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Loc: Essex, UK
Looks like a lot of interesting stuff has been added to this thread. I'm without the internet at present, and will be so for a few days, but I look forward to catching up with this when back on line.
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#43944 - 06/08/12 01:16 PM Re: Earths Water in a Ball [Re: paul]
Orac Offline
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Registered: 05/20/11
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Loc: Currently Illinois, USA
Originally Posted By: paul

since you are a scientist could you please inform us what the new gravity constant is when grace is around.


It has never been an absolute constant nor is the speed of sound or many other science constants.

Gravity was standardized for one reason alone to make all weights uniform so you could trade goods and agree on the the same weight. The weight standard resides in SI in paris and there is actually a funny backstory that it has been losing weight (http://www.msnbc.msn.com/id/20744160/ns/...y-loses-weight/)

Originally Posted By: http://en.wikipedia.org/wiki/Standard_gravity

It is defined as precisely 9.80665 m/s2, or about 35.30394 (km/h)/s (&#8776;32.174 ft/s2 or &#8776;21.937 mph/s). This value was established by the 3rd CGPM (1901, CR 70) and used to define the standard weight of an object as the product of its mass and this nominal acceleration. The acceleration of a body near the surface of the Earth is due to the combined effects of gravity and centrifugal acceleration; the total (the apparent gravity) is about 0.5 percent greater at the poles than at the equator.

Although the symbol g is sometimes incorrectly used for standard gravity, g (without a suffix) strictly means the local acceleration due to local gravity and centrifugal acceleration, which varies depending on one's position on Earth (see Earth's gravity).


That kilogram bar is set against standard gravity.

Now read what Earths gravity is (http://en.wikipedia.org/wiki/Earth%27s_gravity)

So the answer is it is you that has been confused and gravity on earth was never constant, standard gravity definition to define weight is a constant.

At secondary schooling level they probably interchangably use the standard gravity in calculations but standard gravity and earth gravity always have been different and known to be so as far back as the 118 year kilogram standard bar has existed.

You may now be interested to search what things affect the speed of sound because it is not constant either although probably taught as a constant at secondary school :-)


Edited by Orac (06/08/12 01:17 PM)
_________________________
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#43945 - 06/08/12 01:30 PM Re: Earths Water in a Ball [Re: Orac]
paul Offline
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http://www.webmasternow.com/copyandpaste.html

Standard gravity, or standard acceleration due to free fall, usually denoted by g0 or gn, is the nominal acceleration of an object in a vacuum near the surface of the Earth. It is defined as precisely 9.80665 m/s2, or about 35.30394 (km/h)/s (&#8776;32.174 ft/s2 or &#8776;21.937 mph/s). This value was established by the 3rd CGPM (1901, CR 70) and used to define the standard weight of an object as the product of its mass and this nominal acceleration.[1][2][3] The acceleration of a body near the surface of the Earth is due to the combined effects of gravity and centrifugal acceleration; the total (the apparent gravity) is about 0.5 percent greater at the poles than at the equator.
Although the symbol g is sometimes incorrectly used for standard gravity, g (without a suffix) strictly means the local acceleration due to local gravity and centrifugal acceleration, which varies depending on one's position on Earth (see Earth's gravity). The symbol g should not be confused with G, the gravitational constant, or g, the symbol for gram. The g is also used as a unit of acceleration, with the value defined as above; see g-force.
The value of g0 defined above is a nominal midrange value on Earth, originally based on the acceleration of a body in free fall at sea level at a geodetic latitude of 45°. Although the actual acceleration of free fall on Earth varies according to location, the above standard figure is always used for metrological purposes. (The actual average sea-level acceleration on Earth is slightly less.)
[edit]See also

Gravitational acceleration
Metre per second squared
[edit]References

^ The international system of units (SI) – United States Department of Commerce, NIST Special Publication 330, 2001, p. 29
^ The International System of Units (SI) – Bureau international des poids et mesures, 8th edition, 2006, p. 142-143
^ The international system of units (SI) – United States Department of Commerce, NIST Special Publication 330, 2008, p. 57
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Categories: Fundamental physics conceptsGravitationIntroductory physicsUnits of acceleration

The gravitational constant denoted by letter G, is an empirical physical constant involved in the calculation(s) of gravitational force between two bodies. It usually appears in Sir Isaac Newton's law of universal gravitation, and in Albert Einstein's theory of general relativity. It is also known as the universal gravitational constant, Newton's constant, and colloquially as Big G.[1] It should not be confused with "little g" (g), which is the local gravitational field (equivalent to the free-fall acceleration[2]), especially that at the Earth's surface.
Contents [hide]
1 Laws and constants
2 Dimensions, units, and magnitude
3 History of measurement
4 The GM product
5 See also
6 Notes
7 References
8 External links
[edit]Laws and constants

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 (inverse-square law) (r) between them:

The constant of proportionality, G, is the gravitational constant.
The gravitational constant is a difficult physical constant to measure to high accuracy.[3] In SI units, the 2010 CODATA-recommended value of the gravitational constant (with standard uncertainty in parentheses) is:[4]

with relative standard uncertainty 1.2×10&#8722;4.[4]
[edit]Dimensions, units, and magnitude

The dimensions assigned to the gravitational constant in the equation above—length cubed, divided by mass, and by time squared (in SI units, meters cubed per kilogram per second squared)—are those needed to balance the units of measurements in gravitational equations. However, these dimensions have fundamental significance in terms of Planck units; when expressed in SI units, the gravitational constant is dimensionally and numerically equal to the cube of the Planck length divided by the product of the Planck mass and the square of Planck time.
In natural units, of which Planck units are a common example, G and other physical constants such as c (the speed of light) may be set equal to 1.
In many secondary school texts, the dimensions of G are derived from force in order to assist student comprehension:

In cgs, G can be written as:

G can also be given as:

Given the fact that the period P of an object in circular orbit around a spherical object obeys

where V is the volume inside the radius of the orbit, we see that

This way of expressing G shows the relationship between the average density of a planet and the period of a satellite orbiting just above its surface.
In some fields of astrophysics, where distances are measured in parsecs (pc), velocities in kilometers per second (km/s) and masses in solar units (), it is useful to express G as:

The gravitational force is extremely weak compared with other fundamental forces. For example, the gravitational force between an electron and proton one meter apart is approximately 10&#8722;67 newtons, while the electromagnetic force between the same two particles is approximately 10&#8722;28 newtons. Both these forces are weak when compared with the forces we are able to experience directly, but the electromagnetic force in this example is some thirty nine orders of magnitude (i.e., 1039) greater than the force of gravity — roughly the same ratio as the mass of the Sun compared to a microgram mass.
[edit]History of measurement

The gravitational constant appears in Newton's law of universal gravitation, but it was not measured until seventy one years after Newton's death by Henry Cavendish with his Cavendish experiment, performed in 1798 (Philosophical Transactions 1798). Cavendish measured G implicitly, using a torsion balance invented by the geologist Rev. John Michell. He used a horizontal torsion beam with lead balls whose inertia (in relation to the torsion constant) he could tell by timing the beam's oscillation. Their faint attraction to other balls placed alongside the beam was detectable by the deflection it caused. Cavendish's aim was not actually to measure the gravitational constant, but rather to measure the Earth's density relative to water, through the precise knowledge of the gravitational interaction. In retrospect, the density that Cavendish calculated implies a value for G of 6.754 × 10&#8722;11 m3 kg&#8722;1 s&#8722;2.[5]
The accuracy of the measured value of G has increased only modestly since the original Cavendish experiment. G is quite difficult to measure, as gravity is much weaker than other fundamental forces, and an experimental apparatus cannot be separated from the gravitational influence of other bodies. Furthermore, gravity has no established relation to other fundamental forces, so it does not appear possible to calculate it indirectly from other constants that can be measured more accurately, as is done in some other areas of physics. Published values of G have varied rather broadly, and some recent measurements of high precision are, in fact, mutually exclusive.[3][6]
In the January 5, 2007 issue of Science (page 74), the report "Atom Interferometer Measurement of the Newtonian Constant of Gravity" (J. B. Fixler, G. T. Foster, J. M. McGuirk, and M. A. Kasevich) describes a new measurement of the gravitational constant. According to the abstract: "Here, we report a value of G = 6.693 × 10&#8722;11 cubic meters per kilogram second squared, with a standard error of the mean of ±0.027 × 10&#8722;11 and a systematic error of ±0.021 × 10&#8722;11 cubic meters per kilogram second squared."[7]

[edit]The GM product

Main article: Standard gravitational parameter
The quantity GM—the product of the gravitational constant and the mass of a given astronomical body such as the Sun or the Earth—is known as the standard gravitational parameter and is denoted . Depending on the body concerned, it may also be called the geocentric or heliocentric gravitational constant, among other names.
This quantity gives a convenient simplification of various gravity-related formulas. Also, for celestial bodies such as the Earth and the Sun, the value of the product GM is known more accurately than each factor independently. Indeed, the limited accuracy available for G often limits the accuracy of scientific determination of such masses in the first place.
For Earth, using M&#8853; as the symbol for the mass of the Earth, we have

Calculations in celestial mechanics can also be carried out using the unit of solar mass rather than the standard SI unit kilogram. In this case we use the Gaussian gravitational constant which is k2, where

and
is the astronomical unit;
is the mean solar day;
is the solar mass.
If instead of mean solar day we use the sidereal year as our time unit, the value of ks is very close to 2&#960; (k = 6.28315).
The standard gravitational parameter GM appears as above in Newton's law of universal gravitation, as well as in formulas for the deflection of light caused by gravitational lensing, in Kepler's laws of planetary motion, and in the formula for escape velocity.
[edit]See also

Physics portal
Dirac large numbers hypothesis
Accelerating Universe
Gravity expressed in terms of orbital period
Lunar Laser Ranging Experiment
Cosmological constant
Gravitational coupling constant
Strong gravitational constant
[edit]Notes

^ "University of Washington Big G Measurement". Astrophysics Science Division. Goddard Space Flight Center. 2002-12-23. "Since Cavendish first measured Newton's Gravitational constant 200 years ago, "Big G" remains one of the most elusive constants in physics."
^ Fundamentals of Physics 8ed,Halliday/Resnick/Walker, ISBN 978-0-470-04618-0 p 336
^ a b George T. Gillies (1997), "The Newtonian gravitational constant: recent measurements and related studies", Reports on Progress in Physics 60 (2): 151–225, Bibcode 1997RPPh...60..151G, DOI:10.1088/0034-4885/60/2/001. A lengthy, detailed review. See Figure 1 and Table 2 in particular.
^ a b P.J. Mohr, B.N. Taylor, and D.B. Newell (2011), "The 2010 CODATA Recommended Values of the Fundamental Physical Constants" (Web Version 6.0). This database was developed by J. Baker, M. Douma, and S. Kotochigova. Available: http://physics.nist.gov/constants [Thursday, 02-Jun-2011 21:00:12 EDT]. National Institute of Standards and Technology, Gaithersburg, MD 20899.
^ Brush, Stephen G.; Holton, Gerald James (2001), Physics, the human adventure: from Copernicus to Einstein and beyond, New Brunswick, N.J: Rutgers University Press, pp. 137, ISBN 0-8135-2908-5
^ Peter J. Mohr; Barry N. Taylor (January 2005), "CODATA recommended values of the fundamental physical constants: 2002" (PDF), Reviews of Modern Physics 77 (1): 1–107, Bibcode 2005RvMP...77....1M, DOI:10.1103/RevModPhys.77.1, retrieved 2006-07-01. Section Q (pp. 42–47) describes the mutually inconsistent measurement experiments from which the CODATA value for G was derived.
^ J. B. Fixler; G. T. Foster; J. M. McGuirk; M. A. Kasevich (2007-01-05), "Atom Interferometer Measurement of the Newtonian Constant of Gravity", Science 315 (5808): 74–77, Bibcode 2007Sci...315...74F, DOI:10.1126/science.1135459, PMID 17204644
[edit]References

E. Myles Standish. "Report of the IAU WGAS Sub-group on Numerical Standards". In Highlights of Astronomy, I. Appenzeller, ed. Dordrecht: Kluwer Academic Publishers, 1995. (Complete report available online: PostScript; PDF. Tables from the report also available: Astrodynamic Constants and Parameters)
Jens H. Gundlach; Stephen M. Merkowitz (2000), "Measurement of Newton's Constant Using a Torsion Balance with Angular Acceleration Feedback", Physical Review Letters 85 (14): 2869–2872, arXiv:gr-qc/0006043, Bibcode 2000PhRvL..85.2869G, DOI:10.1103/PhysRevLett.85.2869, PMID 11005956
[edit]External links

Newtonian constant of gravitation G at the National Institute of Standards and Technology References on Constants, Units, and Uncertainty
The Controversy over Newton's Gravitational Constant — additional commentary on measurement problems
The Gravitational Constant
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Categories: Celestial mechanicsGravitationFundamental constants


Edited by paul (06/08/12 01:35 PM)
Edit Reason: emphasis sympathy etc
_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#43946 - 06/08/12 01:50 PM Re: Earths Water in a Ball [Re: paul]
paul Offline
Megastar

Registered: 03/21/06
Posts: 4135
here is a video that covers the topic points and valuable descriptive information that you posted on the amount of changes in gravity that causes greenland to rise and the sea level surrounding greenland to sink.



I have read that the detection of differences in gravity are in the millionths of a percentage , in other words worthless to any thing other than sensitive measuring equipment.

_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#43947 - 06/08/12 02:03 PM Re: Earths Water in a Ball [Re: Orac]
paul Offline
Megastar

Registered: 03/21/06
Posts: 4135
Quote:
At secondary schooling level they probably interchangably use the standard gravity in calculations


yes they do , did you know that you can obtain a higher degree of education on the internet.
you should look into these opportunities this way you wont have to guess you will know.

I would have thought that you had attended secondary schooling being a scientist and all but there are age requirements you know.

online education oppurtunities available

Im not saying that a higher education will make you smarter
but it will give you the opportunity to get smarter.

_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#43948 - 06/08/12 02:05 PM Re: Earths Water in a Ball [Re: paul]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
So basically you would rather invent your physics rather than try and understand what actual science has to say.

I don't do pseudo-science or science fiction so my discussion ends here, will leave you to it and your new and improved physics.

You remind me alot of preearth the moment you can't win an argument you start insulting and offensive behaviour like a little child doing a tantrum.

Science arguments are about logic and reasoning not name calling and bad behaviour something both you and pre need to learn. I am not always right and if I am wrong I am easily swayed by a good solid scientific argument especially in areas like this which is way outside my normal area.


Edited by Orac (06/08/12 02:28 PM)
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#43949 - 06/08/12 02:48 PM Re: Earths Water in a Ball [Re: Orac]
paul Offline
Megastar

Registered: 03/21/06
Posts: 4135
I suppose that using microscopic changes in gravity to describe the reason that sea levels surrounding greenland are "sinking"
is science to you then.

but to me it is not science.

it is false science.

there may be some slight unnoticeable millionth of a degree variation in the gravity of greenland because it has lost ice
but the primary cause of greenlands rebounding and the sea level "sinking" surrounding greenland is simply a loss of weight due to ice melt.

which leads me to conclude that you do participate in pseudo-science whether you realize it or not.

Im not saying that grace is false science , what Im saying is that the use of grace data to describe a reason that the sea level surrounding greenland is "sinking" is false science.


_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#43950 - 06/08/12 03:15 PM Re: Earths Water in a Ball [Re: Orac]
paul Offline
Megastar

Registered: 03/21/06
Posts: 4135
#43925
I am confused is this an excercise in ridiculous or are you actually trying to calculate something?
#43938
Then you would be stupidly wrong
There are micro gravity changes around you all the time that you are blissfully unaware of
I am sorry that the actual science of gravity messes with your actual perception
#43944
is it is you that has been confused
#43948
So basically you would rather invent your physics rather than try and understand what actual science has to say.
will leave you to it and your new and improved physics.
You remind me alot of preearth

LOL ...

Quote:
Science arguments are about logic and reasoning not name calling and bad behaviour something both you and pre need to learn.


my video response

_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#43951 - 06/08/12 03:31 PM Re: Earths Water in a Ball [Re: paul]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Originally Posted By: orac

Then you would be stupidly wrong


Is the only comment there that would remotely qualify as offensive or bad tempered.

I actually didn't intended to suggest you were stupid just the understanding should be simple, although I can see with my english skills being so bad (English is not my native language) I conceed now that was poor choice and reading it now you are right I see what I did wrong there.

I am sorry as I read them I can't see how the other statements are in anyway offensive ... is my english that bad?

I cut and post alot for answers so I don't trip over errors in translation but I do find english difficult at times.

Someone once described my english as brutal whatever that means ... what am I doing wrong?


Edited by Orac (06/08/12 03:35 PM)
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

Top
#43952 - 06/08/12 05:36 PM Re: Earths Water in a Ball [Re: Orac]
paul Offline
Megastar

Registered: 03/21/06
Posts: 4135
Quote:
I can see with my english skills being so bad (English is not my native language)


I didnt know you were a foreigner I just thought you were illiterate.
your post state that you are in Australia which has english as
the national language although there are many variants between the structure of American and Austrailian sentences and their
meanings.
still you need to use a little more in your sentences.

ie...

I conceed now that was poor choice
should be
I conceed now that was a poor choice
or
that was a poor choice on my part
etc...

not bad though , keep trying your almost there.

Quote:
Then you would be stupidly wrong


you should have wrote.

then you would be exactly correct as usual.

its a little bit sharper without using words such as stupid.

and attacking ones level of education will leave you wide open to future attacks concerning your level of education.

knowing that a high level of education does not require such
tactics in a discussion, you may find it helpful to refrain from any attack or sarcasm of another posters level of education in the future.

I normally attack my attackers in a manner that is not easily seen as an attack yet delivers a decisive crippling injury.

hope this helps and maybe you need to stop reading web sites so often and read some books where examples of proper english are found.




Edited by paul (06/08/12 05:50 PM)
Edit Reason: literacy , empty space removal , tidyness
_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

Top
#43953 - 06/08/12 07:09 PM Re: Earths Water in a Ball [Re: paul]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Originally Posted By: paul

I didnt know you were a foreigner I just thought you were illiterate.
your post state that you are in Australia which has english as
the national language although there are many variants between the structure of American and Austrailian sentences and their
meanings.


Australia gave me political asylum but I am currently in USA working but still have uni attachment to Australia.


Originally Posted By: paul

hope this helps and maybe you need to stop reading web sites so often and read some books where examples of proper english are found.


Unfortunately that is something I have very little time to do and usually things get lost in translation. I have been given numerous books that are supposedly great but I don't get what makes them great. A friend gave me "Catcher in the Rye" to read and I am really struggling with it.
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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