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Messages - gem

Pages: [1] 2 3 4
1
New Theories / Is it publishing ?
« on: 06/10/2014 18:08:26 »
HI all, on this part of the forum it states : Got a new theory on something? Post your hypotheses here... is this equivalent to publishing ?

2
New Theories / Can gravity make you fat?
« on: 07/05/2010 23:47:25 »
Quote from: Geezer on 06/05/2010 07:24:44
I understand that gravity not only pulls you towards the Earth, but it also exerts a force that tends to pull "outwards"
Yes it causes partial cancellation of gravitational force.

Quote from: JP on 07/05/2010 10:16:12
Why would they get an outward force?  I might be missing it, but if every point on your body is being pulled (as a result of the net force) towards the earth's center,

Quote from: Geezer on 06/05/2010 17:50:53
I think it might be different if you don't treat the Earth as a point mass.

An important point to remember when considering earths force field is that the vector field in question does not exist.

It is only a map of the net vectors which give a direction, a particle in that location in that moment will take.

This only a mathematical tool sometimes called a Kuhnian construct.

The net vector part of the force field is the product of and linked inseparably to the lines of force one object exerts on another object or a collection of other objects from where they actually are. 

meaning that every particle that makes up a human body does indeed have a aspect of outward force in the direction of its interaction with all particles where ever they may be along the lines of force.

May be the shape of the average interaction is the shape of a cone so fortunately only a percentage of this force actually shows up on the bathroom scales,so we don't even have to measure it.

Quote from: Geezer on 06/05/2010 17:50:53

I think it might be different if you don't treat the Earth as a point mass.
Yes last time i looked it didn't appear to be one.

when asked any questions by my other half i have two stock answers 'yes dear' and 'no dear'    "Does this dress make me look fat?"  just better make sure your listening to the question.

3
New Theories / Newton made an error and Einstein copied it
« on: 06/05/2010 22:33:11 »
OK all i know i must be testing your patience, because it seems like i am agreeing with newtons shell theorem on one hand but saying there is an error on the other.

But hang in there and i will try to isolate what i perceive to be the error.

So, shell theorem says that the magnitude of the gravitational force is the same as that of a point mass in the centre of the shell with the same mass taking into account all the vector sums and all the cancellations.

And yes i believe it does, so whats the problem?.

The problem is the gravity force that we measure at the surface of the earth has two aspects  magnitude, and a direction.

And because newton showed with shell theorem that the magnitude of the force was equal to a point mass coming from the centre that has been the assumed to be the direction also.

But shell theorem does not prove direction it proves magnitude of the force.


In your diagram the points A and B if they had opposite points in the other half IE a mirror image you would have two cones under your body of mass on earths surface one cone of average interaction for the northern hemisphere and one cone of average interaction for the southern hemisphere.

So the average direction cone of the force will be some where between the two.

And it is this aspect of the direction of the force that will cause variation.
In that at various distance the increased effectiveness of the force associated with the reduction in angle has to be taken into account.

Because at earths surface there is a force field that is equal to the magnitude of all of earths mass equivalent to that of a point mass in the centre.

Because of its direction we are unable to measure all of its force as weight or gravitational acceleration
 [ Invalid Attachment ]  

4
New Theories / Newton made an error and Einstein copied it
« on: 05/05/2010 19:06:07 »
 


Quote from: Geezer on 04/05/2010 23:08:47
There is no cancellation of any of the components that produce the gravitational effect.

I thought we already covered partial cancellation due to the vector nature of the force,you are contradicting 'JP' 'wikipedia'and it would seem yourself.

Quote from: Geezer on 30/04/2010 21:18:19
I think what you are saying here is that as the object gets further from the earth, the angles will reduce, so the component of the force acting between the centers (the attractive force times the cosine of the angle) will increase with distance.
Assuming I got that right, then yes, I agree it will.

And this
Quote from: Geezer on 30/04/2010 21:18:19
so it's necessary to account for the reduced force associated with distance at the same time as the increased effectiveness of the force associated with the reduction in angle.

The theorem takes that into account,


Because forces are vectors, the affect of an individual force upon an object is often canceled or partially canceled by the affect of another force.

Quote from: Geezer on 30/04/2010 21:18:19
The theorem takes that into account,

Could you show where increased effectiveness of the force associated with the reduction in angle is actually accounted for ?.

5
New Theories / Newton made an error and Einstein copied it
« on: 04/05/2010 22:19:52 »
There is a difference in the following two statements.

Quote from: Geezer on 04/05/2010 05:04:14
The Shell Theorem proves that a spherical object of uniform density produces exactly the same gravitational force as a point object of the same mass.


 I think you will find that shell theorem does not actually prove that, what it proves is.

a spherically symmetric body affects external objects gravitationally as though all of its mass were concentrated at a point at its centre ,after allowing for the partial cancellation due to the vector nature of the force.

IE the value of the cancellation is not included.

In your statement above there is no cancellation so no variation in cancellation at different distances.
So what you posted here does not get considered.


Quote from: gem on 30/04/2010 08:27:08
so to show what is wrong with the maths.
I think that you will find the vector sum arrow in red in JP's diagram , will increase in magnitude relative to the attractive force arrows in black for the 'point mass' object lying along the ring's axis, as the distance from the surface of the sphere increases for all calculations done for any pair of point Masses contained within the sphere acting on the said point mass object. IE a greater percentage of the potential gross force

And this will cause inverse square law violation.
Quote from: Geezer on 30/04/2010 21:18:19
I think what you are saying here is that as the object gets further from the earth, the angles will reduce, so the component of the force acting between the centers (the attractive force times the cosine of the angle) will increase with distance.

Assuming I got that right, then yes, I agree it will. However, the gravitational attraction will also diminish while the distance increases as the inverse of the square of the distance, so it's necessary to account for the reduced force associated with distance at the same time as the increased effectiveness of the force associated with the reduction in angle.


So do you still agree it will?.

JP the error i am highlighting is i don't believe it is possible for the gravitational force to diminish according to the inverse square law. so i am not saying there is a error in his equation.
The error is to think it proved that you could apply inverse square law because of it.

Are you aware of any aspect of accounting for a increased value of the force?

Quote from: Geezer on 30/04/2010 21:18:19
so it's necessary to account for the reduced force associated with distance at the same time as the increased effectiveness of the force associated with the reduction in angle.

The theorem takes that into account,


Does it ?

And if we all agree that the value of gravitational attraction we measure at the earths surface is a vector sum what percentage is the amount of cancellation prior to that net figure at that point?.

What figure does shell theorem give to it, IE what does shell theorem state the gross force is.

6
New Theories / Newton made an error and Einstein copied it
« on: 03/05/2010 17:37:16 »
Quote from: Geezer on 01/05/2010 20:24:45
Gem,

Are you saying that the inverse square law only works for point masses but it is in error when the object has real dimensions (like the Earth for example)?

Yes i believe  a unified field theory requires it.

Which then calls into question the validity of big G.

As its name of gravitational constant becomes a bit of a misnomer because with different density's of of mass but the same value of mass within a homogeneous sphere the angles of attraction will vary, [due to variation in the lengths of radius ] causing tests of gravitational constant to vary.

Quote from: LeeE on 01/05/2010 21:27:27

If Newton et al. got it wrong then it would also seem that the currently accepted mass of the Earth is also wrong.


Yes it would seem so, if you look at the average angles of attraction between the large mass spheres in Cavendish's original experiment and the small mass spheres there respective sizes being approximately 12 inch spheres and 2 inch spheres.

Then their angle of attraction between there respective point masses would be more acute than the comparison that was made between the small lead sphere and the earth.

Meaning that there will have been a greater pro rata value of attraction in the experiment causing a slight under value of the density of the earth.
 
Quote from: LeeE on 01/05/2010 21:27:27
[/ftp]
However, if the accepted mass of the Earth is incorrect then all the stuff we've launched up into orbit wouldn't be where it's supposed to be: geostationary satellites would drift and GPS would be wildly inaccurate.

Geostationary satellites are not used for GPS they are used for communication.

However if your point is one of the altitude that they are supposedly stationary at  and what the value of gravitational acceleration is at that distance in space from the earth then your point is a valid one .

But it is not as easy as just applying the equations as there are large variations in the values of attraction that already exceed the effect i am suggesting.

Because while a geostationary orbit should hold a satellite in fixed position above the equator, orbital perturbations, such as by the Moon, IE the earths orbit around its barycentre, and from the fact that the Earth is not an exact sphere cause slow but steady drift away from the geostationary location. Satellites correct for these effects with station-keeping maneuvers

Quote from: LeeE on 01/05/2010 21:27:27
where...
 G = the gravitational constant = 6.67428e-11
 M = the mass of the Earth (kg) = 5.9736e24
 r = Earth's equatorial radius (m) =  6.3781e6
 a = the resulting acceleration (towards the center of the Earth)

we get an acceleration of -9.800718 m/s2

which, when the centripetal reduction due the the equatorial rotation is taken into account, is just about what is actually measured (the average acceleration at the equator is surface 9.780327 m/s2).

Yes the variation of  measured g  with latitude at sea level ranges from about 9.78 m/s at the equator to over 9.83 at the poles, so allowing for the fact that the radius is 21k/m less at the poles you should get a gravitational acceleration force that is approximately 3 millimetres per/second squared less.

However the recorded measured values don't confirm this and this is thought to be down to the fact that the earth is not a homogeneous sphere and gets denser the closer to the center.
 
Although big G seems to be close to the values at earths surface it is not exact,So not the last word on the matter.

And as i have said earlier in this post it is as the distance from the mass increases that this gross force will manifest itself but it will obviously be diluted by the inverse square of the distance but as a percentage of the force it will not be inconsiderable. 

7
New Theories / Newton made an error and Einstein copied it
« on: 01/05/2010 16:35:49 »
Geezer your last post is right on the crux of the matter.

Quote from: Geezer on 30/04/2010 21:18:19
Quote from: gem on 30/04/2010 08:27:08
so to show what is wrong with the maths.
I think that you will find the vector sum arrow in red in JP's diagram , will increase in magnitude relative to the attractive force arrows in black for the 'point mass' object lying along the ring's axis, as the distance from the surface of the sphere increases for all calculations done for any pair of point Masses contained within the sphere acting on the said point mass object. IE a greater percentage of the potential gross force

And this will cause inverse square law violation.

I think what you are saying here is that as the object gets further from the earth, the angles will reduce, so the component of the force acting between the centers (the attractive force times the cosine of the angle) will increase with distance.

Assuming I got that right, then yes, I agree it will. However, the gravitational attraction will also diminish while the distance increases as the inverse of the square of the distance, so it's necessary to account for the reduced force associated with distance at the same time as the increased effectiveness of the force associated with the reduction in angle.

absolutely right.

Quote from: Geezer on 30/04/2010 21:18:19
       and, it turns out that, regardless of the distance between the Earth and the object, when the forces are all integrated, they produce the same force that would be produced if all the mass of the Earth was concentrated in one point at its center.


absolutely right again i posted this statement much earlier.

'I do not disagree with Shell theorem proving A spherically symmetric body affects external objects gravitationally as though all of its mass were concentrated at a point at its center at various distances in space.'


Quote from: Geezer on 30/04/2010 21:18:19
so it's necessary to account for the reduced force associated with distance at the same time as the increased effectiveness of the force associated with the reduction in angle.

The theorem takes that into account,


this is the crux of the matter i don't believe that at various distance the increased effectiveness of the force associated with the reduction in angle has been taken into account.

I believe what has been done is show , regardless of the distance between the Earth and the object, when the forces are all integrated, they produce the same force that would be produced if all the mass of the Earth was concentrated in one point at its center.
And concluded that therefore it is reasonable to apply inverse square law to a measured value of gravitational acceleration.[so this is the error]

Because as i have pointed out earlier the gravitational acceleration we measure is a vector sum only IE a net figure, at the background of that net force there is a gross force that will manifest a greater percentage of its potential force the more acute gets the angle of interaction.

This is will be demonstrated [as in JPs diagram] by the vector sum arrow in red  increasing in magnitude relative to the attractive force arrows in black for the 'point mass' object lying along the ring's axis, as the distance from the surface of the sphere increases for all  calculations for all point mass pairs calculated from where they are in reality.

8
New Theories / Newton made an error and Einstein copied it
« on: 01/05/2010 15:10:08 »
Quote from: gem on 18/04/2010 11:17:50
I know that newtons theory takes inverse square law from the centre of the earth and it is the value attraction at earths surface that is used, sorry for not making that clearer.

9
New Theories / Newton made an error and Einstein copied it
« on: 01/05/2010 15:09:04 »
Quote from: JP on 30/04/2010 18:03:35
Gem,

I'm still thoroughly confused as to what you're saying Newton claimed.  So let's assume the earth is a uniform sphere. 

1) Are you saying that Newton claimed that the earth's gravity measured above the earth's surface is proportional to the inverse square of the distance between the center of the earth and the object?


10
New Theories / Newton made an error and Einstein copied it
« on: 30/04/2010 12:43:04 »
Quote from: PhysBang on 29/04/2010 21:45:16
Quote from: gem on 29/04/2010 20:40:56
This is because when newton applied inverse square law to the strength of earths gravitational attraction at earths surface he fixed that value as the one to be used at all distances from the surface.
Well, no he didn't. One has only to look at the famous "moon test" of Book III of the Principia to see that the force of gravity on the moon from the Earth is less than that at the surface.



 Its my understanding Newton had worked backwards from a known and relatively accurate value for the rate of fall of objects on Earth and applied inverse square law from earths centre using that value. are you saying he did not?

11
New Theories / Newton made an error and Einstein copied it
« on: 30/04/2010 08:27:08 »
Quote from: PhysBang on 29/04/2010 21:45:16

Except that the centre of the sphere is on the axis of the centre of the rings and, geometrically, it doesn't matter whether or not all the mass is along the axis or concentrated at the centre.


Quote from: Geezer on 29/04/2010 22:42:38


Shell theory proves it's half way across the diameter of the Earth along that line.

If you pretend that all of earths mass is at the centre in a point mass you eliminate this effect from being taken in to account
Quote from: Geezer on 28/04/2010 22:17:01
The force in the direction of the axis is proportional to the cosine of the angle, and the angle varies with distance.


for every point mass contained within the earth as you leave earths surface.

Quote from: Geezer on 29/04/2010 22:42:38
If our point mass is at the "north pole" that means the sum of all the forces along the axis produced by the upper hemisphere is equal to the sum of all the forces produced by the lower hemisphere.

 The theorem proves that without a doubt. If you want to convince anyone that Newton was wrong, you'll have to explain what is wrong with the math.

As you point out it is only the vector sums that equal to the centre ,and as you put space between a point mass and the earth this effect

Quote from: Geezer on 28/04/2010 22:17:01
The force in the direction of the axis is proportional to the cosine of the angle, and the angle varies with distance.

Actually continues to happen.
[because all of earths mass is not concentrated at the centre]

so to show what is wrong with the maths.
I think that you will find the vector sum arrow in red in JP's diagram , will increase in magnitude relative to the attractive force arrows in black for the 'point mass' object lying along the ring's axis, as the distance from the surface of the sphere increases for all calculations done for any pair of point Masses contained within the sphere acting on the said  point mass object. IE a greater percentage of the potential gross force

And this will cause inverse square law violation.

12
New Theories / Newton made an error and Einstein copied it
« on: 29/04/2010 20:40:56 »
Quote from: Geezer on 28/04/2010 22:17:01

 The force in the direction of the axis is proportional to the cosine of the angle, and the angle varies with distance.

Absolutely hold that thought

Quote from: Geezer on 28/04/2010 22:17:01
But how does that disprove the shell theorem?

Because of this statement which is physically impossible
Quote from: gem on 27/04/2010 21:58:16
JP in your diagram,
For the inverse square law to work at different distances away, the force arrows in black have to stay at the same ratio to the vector sum 'arrow in red' for every pair of particles at what ever distance away.

This is because when newton applied inverse square law to the strength of earths gravitational attraction at earths surface he fixed that value as the one to be used at all distances from the surface.

And if you take a close look at all the pairs of point masses even the ones on the far side of the sphere [which we call earth] they are all contributing to the value of the gravitational force that is measured on earths surface at a angle to the axis,
so the attraction is along the axis of the centre of the rings.

Not from the centre of the sphere, IE each point mass attracts from where it is in reality.

Which means the value of gravitational attraction at earths surface is a vector sum only, [ie a net force]  of all the pairs of point masses that make up the rings and disks all the way through the earth.

So if we then bring your statement back in to consideration.

Quote from: Geezer on 28/04/2010 22:17:01

 The force in the direction of the axis is proportional to the cosine of the angle, and the angle varies with distance.


Remembering that what we are measuring on earths surface is only vector sum so only a proportion of the gross force.

So the error is Newton did not allow for the variation in the amount of cancellation due to the vector nature of gravitational attraction when at different distances in space from a mass,when he set the value at earths surface to be the one to be used in all calculations at all distances for the inverse square law.

13
New Theories / Newton made an error and Einstein copied it
« on: 28/04/2010 21:37:54 »
Quote from: JP on 27/04/2010 09:24:27
I can even tell you basically how to do it.  Think about a ring of mass and an object lying along the ring's axis, like I show in the figure.  You know that two points on opposite sides of the ring (shown in red) each pull towards each other with an inverse square law.  When you add the vectors, because of symmetry, the resulting vector points directly towards the center of the ring.  Now you can add up all points around the ring.  Since each point has a corresponding point on the opposite side, the entire force is directed exactly towards the ring's center.  The magnitude of it is pretty easy to calculate as well.

[diagram=588_0]


 'pretty Easy'

 
Quote from: gem on 27/04/2010 21:58:16
JP in your diagram,
For the inverse square law to work at different distances away, the force arrows in black have to stay at the same ratio to the vector sum 'arrow in red' for every pair of particles at what ever distance away.

The above statement is correct otherwise you would have a variation in the value of where the sine accounts for the vector nature of the force and uses the fact that that is the only part of the force (pointing towards the earth's center) that isn't canceled by another force.

 But i will make it even easier could anyone point out any pair of point masses on any of the rings that make up a sphere where  the force arrows in black stay at the same ratio to the vector sum 'arrow in red' at what ever distance away.
[other than on the rings axis]

I think that you will find the vector sum arrow in red will increase in magnitude relative to the attractive force arrows in black for the 'point mass' object lying along the ring's axis, as the distance from the surface of the sphere increases for all your calculations.

Making a mockery of applying inverse square law to the value of attraction at the surface of the sphere.

And also can anyone highlight any pairs of point masses on any of the rings that make up a sphere that travel the same distance from the object mass as the centre of the ring. [other than on the rings axis]

Also Making a mockery of the symmetry of the sphere argument as well as applying inverse square law to the value of attraction at the surface of the sphere.

14
New Theories / Newton made an error and Einstein copied it
« on: 27/04/2010 21:58:16 »
Quote from: JP on 27/04/2010 04:47:48

This is all gravitational force?  The forces between points of mass all still follow a r-2 law, which I think we're agreeing on. 

Yes every particle follows inverse square law


Quote from: Geezer on 27/04/2010 06:13:16
Newton never said you can neglect the angles did he? Only when the two objects are sufficiently distant can you use an approximation and assume that all the forces act between the centers of mass of the objects.
There is no allowance for the change in angle of interaction from earths surface to a hundred earths radius's away in the way the strength of earths gravity field is calculated at present.

JP in your diagram,
For the inverse square law to work at different distances away, the force arrows in black have to stay at the same ratio to the vector sum 'arrow in red' for every pair of particles at what ever distance away.

15
New Theories / Newton made an error and Einstein copied it
« on: 26/04/2010 23:22:34 »
[diagram=585_0][diagram=586_0]

OK Geezer in diagram 1 we have a overhead view of two one newton forces acting on a one KG weight on a frictionless surface at 90 degrees to each other giving a net resulting acceleration of 1.4 metres per second squared so 70 percent of the gross input potential.

And in diagram 2 we have the same 1 newton forces acting on the 1 KG weight at a angle of 45 degrees  to each other giving a net resulting acceleration of 1.8 metres per second squared so 90 percent of the gross input potential.
[diagram=587_0]

And in diagram 3 we have a example of the angle of interaction getting more acute and any mass that is not in line with the centre line C/L Note, As the distance between the mass of the two bodies changes only the particles that are in a direct line with the centre to centre actually travel the distance prescribed by inverse square law relative to each others centres.

16
New Theories / Newton made an error and Einstein copied it
« on: 25/04/2010 18:24:08 »
If what i have postulated here as regards the variation in the partial cancellation due to the vector nature of the force, and that there is also a variation in the leftover component (in the direction pointing toward m),is correct.

And as the leftover component is what we measure as gravitational acceleration at earths surface.

It means that when newton took the value of g at earths surface where the partial cancellation will be greatest and said that you could then apply inverse square law to that value from earths centre, is the error.

Because the physical reality's will not allow it to be so.IE for that value to diminish in accordance with inverse square law.

And i believe this is what they have been detecting when studying the results of the experiments done since Cavendish did his first experiment to present day.

Below is an extract from a paper from this area of science
(see http://physics.uci.edu/gravity).

   1 Introduction
In 1974 Daniel Long published a paper Why do we believe Newtonian gravitation at laboratory
dimensions? (Long 1974), comparing measurements of G made since 1894 with
various mass separations r. His plot of G values as a function of r strongly suggested a
dependence on mass separation. Two years later, Long reported an experiment of his own
(Long 1976) which used a torsion balance to compare the forces produced by source masses
at distances of 4.5 cm and 29.9 cm. Long’s experiment used ring-shaped source masses,
exploiting the fact that the force on a test mass at a certain point on the axis of a ring source
mass is at an extremum and thus is quite insensitive to error in its position relative to the
ring. Daniel Long reported that the ratio of the torque produced by the more distant ring to
that produced by the nearer ring exceeded the Newtonian prediction by (0.37 ± 0.07)%, a
result consistent with the distance dependence found in his analysis of G measurements.

Quote from: Geezer on 24/04/2010 08:32:54
So Newton was right then?

That Geezer is THE question

17
New Theories / Newton made an error and Einstein copied it
« on: 24/04/2010 08:26:59 »

Quote from: JP on 23/04/2010 05:21:50
(Note the sentence beginning "However, since there is partial cancellation due to the vector nature of the force, the leftover component (in the direction pointing toward m) is given by. . .")

Yes thanks for that JP i quoted that very extract in my first post on this thread, but have got side tracked defending that there is partial cancellation and showing the amount of that partial cancellation varies at different angles of interaction.

Quote from: JP on 23/04/2010 05:21:50
Quote from: gem on 22/04/2010 22:40:47
The partial cancellation will be greatest at earths surface diminishing the further out in to space,    
You're right about vector sums. 

So from that can i read that you agree that the partial cancellation will be greatest at earths surface diminishing the further out in to space,?


Quote from: JP on 23/04/2010 05:21:50
However, as the posters here have been trying to tell you, this is exactly what Newton did, and this is exactly what the Shell theorem does.

Yes i believe it does this was my reply on the same point to yourself.

Quote from: gem on 20/04/2010 20:00:13
I do not disagree with Shell theorem proving A spherically symmetric body affects external objects gravitationally as though all of its mass were concentrated at a point at its center at various distances in space.

but with the caveat that if there is a variation in the partial cancellation due to the vector nature of the force, it therefore follows that there is a variation in the leftover component (in the direction pointing toward m).

And the leftover component is what we measure as gravitational acceleration at earths surface.

So it seems you cannot just take the value of g at earths surface and apply inverse square law out in to space because you are putting a fixed value on to something that actually varies at different angles of interaction. 

Making shell theorem results specific to each point that they are calculated only.

18
New Theories / Newton made an error and Einstein copied it
« on: 22/04/2010 22:40:47 »
Quote from: Geezer on 22/04/2010 08:14:06
Well in that case you are applying a force of 2N to the 1kg in a direction parallel with the frictionless surface, and there is no need to discuss vectors at all.

If two or more forces act on the same body,on a frictionless surface and these forces are not parallel with each other then the acceleration of the body is written as the vector sum.

And the gravitational acceleration that we experience on earths surface is the vector sum of the attractive force of earths mass

Since there is a partial cancellation of vector forces it then follows there is a partial cancellation in the forces that give earths gravitational resultant force expressed as the acceleration.

And there will be variation in the amount of cancellation due to changes in angle that earths mass attracts a body at different distances from earths surface

The partial cancellation will be greatest at earths surface diminishing the further out in to space, where as the cancellation becomes total within a shell of homogeneous mass.   

Because the net gravitational forces acting on a point mass from the mass elements of the shell totally cancel out.

19
New Theories / Newton made an error and Einstein copied it
« on: 22/04/2010 08:01:35 »
Quote from: Geezer on 22/04/2010 00:46:38
I do not agree. I think you will have a resulting acceleration of 1 m/s^2 in a direction parallel with the frictionless surface.

You would have no acceleration at 90 degrees to the frictionless surface.

All the forces i have described in the example are parallel with the frictionless surface,the change in angle is relative to the standard 1 kg mass.

To give a example of the variation in the amount of cancellation due to the vector nature of gravitational attraction when at different angles

because as i said before

Newton did not allow for the variation in the amount of cancellation due to the vector nature of gravitational attraction when at different distances in space from a mass.


20
New Theories / Newton made an error and Einstein copied it
« on: 21/04/2010 23:35:48 »
Quote from: Geezer on 20/04/2010 22:50:38
As I mentioned earlier, you really are trying to account for all the individual gravitational attractions between all the atoms of the two bodies, because that is the gravitational model. You then have to figure out a mathematical way of doing that. I may be wrong, but I suspect that's exactly what Newton did.

I don't disagree,this was my reply on the same point to yourself.

Quote from: gem on 19/04/2010 17:48:33
newton already overcame that problem with shell theorem which gives gravitational simplifications that can be applied to objects inside or outside a spherically symmetrical body.
 

And also to JP

Quote from: gem on 20/04/2010 20:00:13
I do not disagree with Shell theorem proving A spherically symmetric body affects external objects gravitationally as though all of its mass were concentrated at a point at its center at various distances in space.

and on this point

Quote from: Geezer on 20/04/2010 22:50:38
Because the 3 N and 4 N forces are at right angles to each other, there is no component of either force that can be simply added. It would only be legitimate to simply add them together and say the total force is 7 if both forces acted in the same direction.

correct the net result is 5 metres per second squared.
The gross value of the force is 7 newtons.

Quote from: Geezer on 20/04/2010 22:50:38
There is no "cancellation".

Incorrect, this is a extract from wikipedia on newtons shell theorem.
'However, since there is partial cancellation due to the vector nature of the force,'
http://en.wikipedia.org/wiki/Shell_theorem

If you had 1 newton force acting on a standard 1 kg mass on a frictionless surface in one direction and another 1 newton force acting at 90 degrees to that force you would have a gross force of two newtons and a resulting net acceleration of 1.4 metres per second squared.

if you changed the angle of the forces to 45 degrees you would have 2 newtons of gross force still, and a resulting net acceleration of 1.8 metres per second squared.

And if you changed the angle to 22.5 degrees you would have 2 newtons of gross force  and a resulting net acceleration of 1.95 metres per second squared.

I respectfully suggest people need to take a look at the average vector angle at earths surface where we take the value that we use for the inverse square law and consider how that angle changes the further the distance in to space

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