Proof of the apple 'pulling' the earth?

[plane]

plane:

What do you think about my thought experiment:

Rather think it is avoiding the issue. To indulge you, underpinning what you are ‘thinking’, is the question of what happens when two masses are precisely equal if a small mass does not attract a large mass. Iceaura, you are on the same theme.

There can never be two masses that are precisely the same is the first point to make. But if they were precisely the same, neither would attract the other. That is on simple mathematical reasoning.

Suppose I have two 1-kilogram masses in space, side by side. Then, I add 1 gram to mass number 1. Mass number 1 is then bigger than mass 2, so by your argument, mass 2 is attracted by mass 1's gravity, but mass 1 doesn't attract mass 2 at all. On the other hand, if I added the 1 gram to mass 2 instead, the opposite would happen. Is that what you're claiming? In other words, what determines the entire attraction is not the 1000 grams of mass in each object we started with, but really the 1 gram that is added at the end? Does that not seem a little strange to you?

Why would it seem strange to me? I do invite you to address the rest of my original reply to you. Beginning with an explanation of the physics of a word you used. That is when you employ the term pull with respect of gravity, what do you mean in terms of physics.

Also

The earth’s rate of acceleration due to gravity at sea level and under the moon = 9.8 m/s/s. The moon’s gravity in the same vicinity = 0.0003 m/s/s (approx).

Resultant rate of acceleration at an ocean under the moon = 9.7997 m/s/s.

Which is a lesser weighting of an ocean towards the centre of the earth than what would be the case if the moon wasn’t present. Thus a high tide under the moon.

Presuming you are okey doke with that, it is just simple mathematical analysis of the situation so you should be, it is not mathematical evidence of the moon pulling the ocean or the earth. Thus is not evidence of a smaller mass ‘pulling’ a larger mass. It is just evidence of opposite directions of gravity interacting. There is no ‘pull’ whatsoever involved.

Not thought experiments, that is really where the issue of the thread is at.

The Earth is in orbit around the Sun. Without going a lot deeper into orbital mechanics, this can be simply described as a tug of war between the Earth's natural tendancy to fly off in a straight line and the Sun's gravity. For a circular orbit this tug of war is perfectly balanced and the Earth manitains a constant distance from the Sun. The moon simply upsets this balance. When it is outside of the Earth, its pull tips things very slighty in favor of the Earth traveling in a straight line and the Earth starts to drift slowly away from the Sun. When it is on the inside, it tips things in favor of the Sun and the Earth drifts slowly towards the Sun. This causes the Earth to weave in and out from the Sun.
The fact that the Sun's gravity on the Earth is so much stronger than the Moon's is not a factor as the Sun's gravity pull on the Earth is "all used up" just holding the Earth in orbit. .

‘All used up’. In the language of the age lol. Sorry about that. I know what you are trying to say but whatever way you try and spin it with words, when you add the sun and moon rates of acceleration together at the distance from the sun that the earth is, you get a resultant rate towards the sun. Look Newton has left us a pretty confusing lot. You want the earth to be falling towards the sun and the moon at the same time. Your trouble is no-one has ever observed anything falling both up and down simultaneously. The situation is the earth would be falling towards the sun at a lesser rate because of the moon, but not towards the moon at all, if you were on the right track.

False analogy, as you are trying to make the second axis located at a physical point of the wheel and this is not the case. Here's a more accurate analogy. Put one rod through the center hub hole. After the rod extends out the bottom bend it at a right angle. Then at a pont equal to the distance of one of the stud holes from the center of the wheel bend it at a right angel in the downward direction (away from the wheel). This gives you something that looks like a crank. The part of the rod sticking through the wheel is the "handle" of the crank and the part extending downward is its axis of rotation. The wheel can both spin on the handle and the crank can turn (carrying the axis of the turning wheel in a circle at the same time. The two motions are indendent of each other.

No. It’s a good analogy. You cheat with your second right angle. It comes back towards the wheel and through the wheel.

You do realise that the Moon produces two tidal bulges? There is a high tide bulge on the side directly under the Moon as well as one on the side opposite that of the Earth. This is why high tides are a roughly 12.5 hrs apart rather than roughly 25 hrs apart.

Your "lessening of opposite directions of gravity interacting" theory doesn't fit this fact, as on the opposite side of the Earth the gravities would work in the same direction, increasing the acceleration due to gravity, and causing a low tide rather than a high tide.

What does explain it is the differential pull of the Moon across the diameter of the Earth. The near side of the Earth feels a stronger pull from the Moon than the center of the Earth does and the far side even less than the Center. This difference creates a net pull that tends to stretch the oceans (and to a certain extent the Earth itself) along a line that joins the Earth and Moon, causing the two tidal bulges.

Well aware that there is like tides on direct opposite sides of the earth. My lessening of opposite directions gravity fits perfectly with there being a high lunar tide on the direct opposite side. The first issue, though, is the one on the moon side.

Like JR, you use the term ‘pull’. A push is an exertion of mass upon mass. Can you define the physics of a pull. All we really know about gravity is that it is an acceleration through space towards the centre of a mass. What is this pull you cite.

 

[iceaura]

Iceaura, you are on the same theme.

I had two other questions, different.

One is how you explain the wobble of the earth's solar orbit, in synchrony with the moon's orbit of the earth.

The other was how the smaller mass identified itself as such, and the larger one knew it was the one that should be pulling. Wouldn't therre have to be some kind of distance guage ?

 

[James R]

plane:

When the moon is outside the earth’s orbit (further from the sun than the earth), how does the weaker moon gravity overcome the sun gravity.

It doesn't. Both the Moon and the Earth have a net force towards the Sun at all times. They share an orbit around the Sun.

And that’s before we get to the question of the earth spinning on two axes concurrently. For example get a car wheel. Put a rod through each of two stud holes. Then try and get the wheel to spin around both concurrently.

I don't understand what you're talking about here. The Earth only spins around one axis - the one through the poles.

You use an interesting word three in and further on as well. Can you explain the physics of a ‘pull’? A push is an exertion of one particle upon another. But just what is the description of the pull. The term appears constantly during gravity discussions but just what is it?

There are only four fundamental interactions in the universe: the strong and weak nuclear interactions, electromagnetism and gravity. All manifestations of force result from one of these interactions.

Gravity is a purely attractive interaction. Every mass in the universe attracts every other mass. In contrast, electrostatic forces, for example, can be either attractive or repulsive, depending on the electrical charges involved. But both gravity and electromagnetic forces are non-contact forces. In other words, things don't need to physically touch in order to feel these forces. This is an obvious truth.

The terms "push" and "pull" are not terms that always have well-defined meanings in physics. When they are used, simply apply your common sense and you ought to be able to convert them so that you know whether an attractive or repulsive interaction is being discussed. In the case of gravity, things are simple, because gravity is always attractive.

Hence, when somebody says "The moon's gravity pulls on the Earth", you can read that as "The Earth and Moon interact gravitationally, such that each attracts the other."

Does that make sense?

'Creates' is a word with a bit of license to. How does the moon create tides on earth?

Have you read the standard Newtonian explanation of the tides, involving centre-of-mass of the Earth-moon system, the mutual gravitational force and the centrifugal or centripetal force associated with their orbits around the centre-of-mass?

Forgive me if you did not follow what I posted.

The earth’s rate of acceleration due to gravity at sea level and under the moon = 9.8 m/s/s. The moon’s gravity in the same vicinity = 0.0003 m/s/s (approx).

Resultant rate of acceleration at an ocean under the moon = 9.7997 m/s/s.

Which is a lesser weighting of an ocean towards the centre of the earth than what would be the case if the moon wasn’t present. Thus a high tide under the moon.

Presuming you are okey doke with that, it is just simple mathematical analysis of the situation so you should be, it is not mathematical evidence of the moon pulling the ocean or the earth.

How do you account for the "lesser weighting of the an ocean towards the centre of the earth" then? What's causing the lesser weighting? Does it have anything to do with the moon?

I do appreciate that you are putting a bit of faith in binary stars as proof of an apple attracting the earth but you can perhaps see that if the high tide under the moon is not evidence of apple attracting the earth, then perhaps binary stars and the like aren't either. Also happy to discuss your theoretical reasons if you want, but we probably should get the high tide under the moon out of the road first. It simply is not evidence of an apple attracting the earth.

I'm not sure you understand what causes tides, so perhaps you picked a difficult example. In that case, it might be better to start with the basics of action-reaction force pairs and so on, as I touched on in my initial reply. Tides are complicated because they involve not only gravity but also the fact that the Earth and moon are orbiting a common centre of mass.

How do you account for the high tide on the side of the Earth opposite the moon, by the way?

Rather think it is avoiding the issue. To indulge you, underpinning what you are ‘thinking’, is the question of what happens when two masses are precisely equal if a small mass does not attract a large mass. Iceaura, you are on the same theme.

There can never be two masses that are precisely the same is the first point to make. But if they were precisely the same, neither would attract the other. That is on simple mathematical reasoning.

Standard physics says that if they were both exactly the same, then both would attract the other, just as they do when their masses are different. Can you give any reason why you expect gravity to suddenly switch off if two masses happen to become equal?

For example, suppose I have a 1 kg mass and a 1.1 kg mass. According to you, the 1 kg mass is attracted to the 1.1 kg mass, which presumably just sits still. Now, suppose a piece of dust lands on the 1 kg mass, making its mass 1.1 kg. Suddenly, there is no attraction at all? Now, another piece of dust lands on the same mass, making it 1.2 kg. Suddenly, it stays still and attracts the other mass, and gravity swaps direction?

Can you give any theoretical or observational reason why we ought to believe this?

Look Newton has left us a pretty confusing lot. You want the earth to be falling towards the sun and the moon at the same time. Your trouble is no-one has ever observed anything falling both up and down simultaneously. The situation is the earth would be falling towards the sun at a lesser rate because of the moon, but not towards the moon at all, if you were on the right track.

This is a matter of being careful with reference frames. If you view the situation from the Sun, both the Moon and Earth fall towards the Sun. But if you're on Earth then you're in an accelerating reference frame in which both the Earth and Moon are in free fall around the Sun and you must "subtract off" the Sun's gravitational effect to get the Moon's motion with respect to the Earth. I suspect you may find this difficult to follow. If so, please forgive me and hopefully we'll get there after a bit more discussion. This is why I think we need to start with the basics of force, rather than jump straight into tidal effects and the like.

May I ask how much physics you have studied formally? That way, I'll be better able to tailor my responses so as not to either confuse or patronise you.

 

[Asguard]

james sorry if this is a stupid question. if there are only those 4 forces which is a true "push". ie if i walk up to you and push you over which one of the 4 forces am i exerting on you?

 

[BenTheMan]

Largely electromagnetic.

Although this is somewhat of a trick question because you are not a fundamental object, despite what you think.

The answer can get as complex as you'd like, but basically the atoms in your hand form bonds that are not easily broken.

 

[D H]

if there are only those 4 forces which is a true "push". ie if i walk up to you and push you over which one of the 4 forces am i exerting on you?

That push is an example of the normal force (the same thing that keeps you from sinking into the ground or from walking through walls). The normal force in turn is an example of the electromagnetic force. To be a bit too anthropogenic, the electrons in your body do not want in the same place as the electrons in my body. In fact, they cannot be in the same state per the Pauli exclusion principle. When electrons start getting close to violating this principle they exchange virtual photons to transfer momentum from one electron to the other.

 

[Asguard]

interesting, always wondered what inertal colisions actually WERE

 

[plane]

I had two other questions, different.

One is how you explain the wobble of the earth's solar orbit, in synchrony with the moon's orbit of the earth.

The other was how the smaller mass identified itself as such, and the larger one knew it was the one that should be pulling. Wouldn't therre have to be some kind of distance guage ?

You have wobble as proof of a smaller mass pulling a larger mass? When the physical relationship between mass and gravity is not understood there could easily be a different explanation.

Not a matter of the smaller mass identifying its self and yes, opposite directions of the inverse square law provide a distance gauge. At some point between adjacent masses the direction of fall alternates. From that point going towards the larger mass, there is no direction of fall towards the smaller mass. Thus it is mathematically impossible for a smaller mass to attract a larger mass. You can work that out for your self but, look, I am just after the accepted proof of apple attracting the earth. If you want to go with the wobble, I’ll mark that down.

plane:



It doesn't. Both the Moon and the Earth have a net force towards the Sun at all times. They share an orbit around the Sun.

If it doesn’t why does the earth move away from the sun and towards the moon. That does not appear to be a sensible answer to the problem.

I don't understand what you're talking about here. The Earth only spins around one axis - the one through the poles.

The earth and moon are supposed to be turning around a common centre of gravity, one that is located within the earth.

There are only four fundamental interactions in the universe: the strong and weak nuclear interactions, electromagnetism and gravity. All manifestations of force result from one of these interactions.

Gravity is a purely attractive interaction. Every mass in the universe attracts every other mass. In contrast, electrostatic forces, for example, can be either attractive or repulsive, depending on the electrical charges involved. But both gravity and electromagnetic forces are non-contact forces. In other words, things don't need to physically touch in order to feel these forces. This is an obvious truth.

The terms "push" and "pull" are not terms that always have well-defined meanings in physics. When they are used, simply apply your common sense and you ought to be able to convert them so that you know whether an attractive or repulsive interaction is being discussed. In the case of gravity, things are simple, because gravity is always attractive.

Hence, when somebody says "The moon's gravity pulls on the Earth", you can read that as "The Earth and Moon interact gravitationally, such that each attracts the other."

Does that make sense?

You used the term pull. You still haven’t explained what one is. Noting your shift in language, can you describe the physics of ‘attraction’. Or, perhaps more to the point, can you explain how mass causes an acceleration towards its centre..

How do you account for the "lesser weighting of the an ocean towards the centre of the earth" then? What's causing the lesser weighting? Does it have anything to do with the moon?

Of course it does. I have posted the arithmetic for you. Please go back to it if you are at all interested.

I'm not sure you understand what causes tides, so perhaps you picked a difficult example. In that case, it might be better to start with the basics of action-reaction force pairs and so on, as I touched on in my initial reply. Tides are complicated because they involve not only gravity but also the fact that the Earth and moon are orbiting a common centre of mass.

How do you account for the high tide on the side of the Earth opposite the moon, by the way?

In one breathe unsure that I understand the cause of the tides and next having the confidence to ask me how the high tide on the side of the earth away from the moon is caused. Interesting.

Newton’s third law is how I account for the second high tide but at this stage can’t you understand the difference between the earth’s gravity being slightly less under the moon because of the opposite direction of the moon’s gravity and water falling towards the moon. The difference isn’t even really subtle. If you can’t understand that, I’ll see about posting a diagram to explain it for you. Critical point. If you are genuinely interested in the tides, you won't pay it lip service.

Standard physics says that if they were both exactly the same, then both would attract the other, just as they do when their masses are different. Can you give any reason why you expect gravity to suddenly switch off if two masses happen to become equal?

Not suddenly switch off. Still be a direction of fall of each towards each but not beyond the point that is mid way between the two.

For example, suppose I have a 1 kg mass and a 1.1 kg mass. According to you, the 1 kg mass is attracted to the 1.1 kg mass, which presumably just sits still. Now, suppose a piece of dust lands on the 1 kg mass, making its mass 1.1 kg. Suddenly, there is no attraction at all? Now, another piece of dust lands on the same mass, making it 1.2 kg. Suddenly, it stays still and attracts the other mass, and gravity swaps direction?

Can you give any theoretical or observational reason why we ought to believe this?

Refer to the above answer. You are presuming gravity is an indefinite extension. That doesn’t stand up to mathematical scrutiny.

This is a matter of being careful with reference frames. If you view the situation from the Sun, both the Moon and Earth fall towards the Sun. But if you're on Earth then you're in an accelerating reference frame in which both the Earth and Moon are in free fall around the Sun and you must "subtract off" the Sun's gravitational effect to get the Moon's motion with respect to the Earth. I suspect you may find this difficult to follow. If so, please forgive me and hopefully we'll get there after a bit more discussion. This is why I think we need to start with the basics of force, rather than jump straight into tidal effects and the like.

May I ask how much physics you have studied formally? That way, I'll be better able to tailor my responses so as not to either confuse or patronise you.

Thanks for your rather somewhat impertinent thoughtfulness but as per my initial post in this thread, I am just after what you consider to be proof of an apple attracting the earth. What do you have marked down as proof. The post of mine you are responding to with the above was directed at the question of the earth’s crisscross of its solar orbit as the moon orbits the earth, not the physics of the moon’s orbit of the earth.

So what do you see as proof of a smaller mass attracting a larger mass. Mathematically the theory can be pulled to bits.

Ben the man, could I ask you why you haven’t provided information about what has been measured in a lab. As per post 16/17

 

[BenTheMan]

Ben the man, could I ask you why you haven’t provided information about what has been measured in a lab. As per post 16/17

It doesn't matter what evidence I provide---you've already made your mind up about it.

This is, of course, how crackpots do science.

People have already tried to explain these things to you...there's little I can do to save you from your own ignorance.

 

[plane]

it is measured in the lab.

Are you saying my mind is wrong because you can't explain what you mean here?

You actually misunderstand, anyway. Perhaps its my fault but I'm not really here to argue. Just trying to find reasons people believe an apple attracts the earth.

If you have knowledge of Cavendish type experiment where a large mass is observed to move towards a small mass in a lab, let nothing stop you from presenting it is the point. If your bluff, your bluff.

My mind at this stage says there is no evidence to consider that an apple attracts the earth.

And, if you want to get personal, the evidence would seem to be that your mind is made up in favour of the apple.

I don't need to explain it

When I read that I will concede that I doubted whether or not you had serious evidence.

Anyway so far we have the earth's crisscross of it's solar path in tune with the moon's orbit of the earth as considered proof of a small mass attracting a large mass. And a mention of binary star systems,

Any other.

 

[BenTheMan]

Ok.

You're right.

Maybe you should publish this result in a paper that is more prestigious than our lowly forum.

 

[plane]

Thanks ben for acknowledging that I'm right. Here is a diagram for others.

 

[Steve100]

plane; if you imagine the sun, the moon, and the earth all attached to each other with strings, and all pulling on there strings it might help you to understand gravity.

Just because two people are pulling there strings attached to me from different sides doesn't mean i have to go both directions simultaneously, I merely go in the direction of the net force, same with gravity.

Ok now i can see your diagram I don't understand it, mind explaining?

 

[James R]

plane:

Not a matter of the smaller mass identifying its self and yes, opposite directions of the inverse square law provide a distance gauge. At some point between adjacent masses the direction of fall alternates. From that point going towards the larger mass, there is no direction of fall towards the smaller mass. Thus it is mathematically impossible for a smaller mass to attract a larger mass.

This "direction of fall" you talk about is the direction a third object would fall, towards one or the other of the two gravitating objects. The assumption, of course, is that the third object is not massive enough to significantly perturb the system.

Where you go wrong is in jumping from the behaviour of a third body to conclusions about the original 2-body system.

It doesn't. Both the Moon and the Earth have a net force towards the Sun at all times. They share an orbit around the Sun.

If it doesn’t why does the earth move away from the sun and towards the moon.

It doesn't. The Earth is always falling towards the Sun.

I don't understand what you're talking about here. The Earth only spins around one axis - the one through the poles.

The earth and moon are supposed to be turning around a common centre of gravity, one that is located within the earth.

You're not being precise enough. There are actually three separate effects here. One is the intrinsic spin of the Earth around its axis; another is Earth's orbital motion about the centre of mass of the Earth-moon system; the third is the Earth's orbital motion around the Sun. These three motions are independent and have three different rotational axes.

You used the term pull. You still haven’t explained what one is.

I explained carefully to you that "pull" is just one way to denote an attractive force.

Noting your shift in language, can you describe the physics of ‘attraction’. Or, perhaps more to the point, can you explain how mass causes an acceleration towards its centre.

Nobody can explain why gravity is an attractive force. It just is. All observation confirms it. It's just an observed feature of our universe. You can imagine a universe where things fall up instead of down, but that's not our universe, obviously.

In one breathe unsure that I understand the cause of the tides and next having the confidence to ask me how the high tide on the side of the earth away from the moon is caused. Interesting.

I was trying to ascertain how much you understand about tides.

Newton’s third law is how I account for the second high tide...

I don't understand. Newton's third law concerns equal and opposite forces on different bodies. How does it explain the second high tide?

You are presuming gravity is an indefinite extension. That doesn’t stand up to mathematical scrutiny.

This is a basic error on your part.

All observational data supports the inference that gravity is an inverse-square force. It follows automatically that it has "indefinite extension".

Thanks for your rather somewhat impertinent thoughtfulness but as per my initial post in this thread, I am just after what you consider to be proof of an apple attracting the earth. What do you have marked down as proof.

My "proof" is:

1. Newton's third law states that for every force there is an equal and opposite force.
2. Therefore, when two bodies interact, if one exerts a force F on the other, the other exerts an equal force F on the first, but in the opposite direction.
3. Gravity is a force (in the Newtonian picture).
4. No known experiment with force has ever violated Newton's third law.
5. Therefore, if the Earth pulls on an apple, the apple must pull back on the Earth with an equal and opposite force.

That's really all the "proof" that is needed.

Of course, there's also a lot of direct evidence, such as the kind of astronomical evidence cited previously.

So what do you see as proof of a smaller mass attracting a larger mass. Mathematically the theory can be pulled to bits.

Show me.

 

[temur]

Thanks ben for acknowledging that I'm right. Here is a diagram for others.

This picture is true only for smaller masses present nearby the two bodies, assuming that the two bodies are motionless. It does not show at all what forces the two bodies themselves experience.

Think about this: The Earth is made of many atoms, and any atom is smaller than an apple. So the apple pulls the Earth.

 

[Yorda]

Gravity is a purely attractive interaction.

Maybe it only seems so for us because we're so close to earth. Things that are further away, like the moon, might be repulsed by the earth. I have two magnets, a strong magnet and a weak magnet... when I try to put together north and north pole, they repel, but when i bring them closer, the north and north are attracted.

All objects are made of magnetic particles so for me it seems logical that all objects would be magnetic.

 

[James R]

Yorda:

Maybe it only seems so for us because we're so close to earth. Things that are further away, like the moon, might be repulsed by the earth.

No. The moon's orbit is exactly what we would expect given purely attractive gravity.

I have two magnets, a strong magnet and a weak magnet... when I try to put together north and north pole, they repel, but when i bring them closer, the north and north are attracted.

Impossible. Two north magnetic poles always repel one another.

All objects are made of magnetic particles so for me it seems logical that all objects would be magnetic.

There are three types of magnetism, known as paramagnetism, diamagnetism and ferromagnetism. All objects are somewhat diamagnetic, but those effects don't show up in the ordinary course of events. The usual magnets you would be familiar with are ferromagnets, and only materials containing iron or a couple of other elements are ferromagnetic at all.

Moreover, magnetism and gravity are completely different forces. Magnetism relies on electrical charges interacting, whereas gravity is associated with mass. Gravitational attraction is not magnetic.

 

[andbna]

Think about this: The Earth is made of many atoms, and any atom is smaller than an apple. So the apple pulls the Earth.

Indeed, Plane, your major problem is the assumption that both the apple and the earth are fundamental objects; they aren't.
Consider this (a reductio ad absurdem if you will).
1 Hydrogen atom is smaller than a planet, agreed? Therefore, by your theory, said planet pulls on the hydrogen atom, but the hydrogen has no pull on the planet.
This applies for every lone hydrogen atom.
Interstellar Nebula consist of lone hydrogen atoms.
Therefore, a planet pulls on a nebula, but a nebula does not pull on a planet.
But... observations show that nebula have significant gravitational influences on other interstellar bodies. How is this possible unless the smaller object does indeed pull on the larger object?

Alright, so now you say 'but the nebula is the bigger object!'
Now, a nebula is a region of space populated by a higher density of gases, when compared to other areas; (the density is still extremely small however,) usually hydrogen and helium, though some other elements, or molecules; but, ignoring the question this raises (at what density is gas then considered an object?) let's continue the argument.
So the nebula is the bigger object, the nebula pulls on the planet (as observed) and the planet does not pull on the nebula.
Newton’s first law states that unless the nebula is acted upon by an external force, it will stay in its current motion.
Thus, the nebula should be unaffected by our planet.
But this doesn’t happen! Instead as the planet approaches the nebula, a bit of it is pulled away towards our planet! Clearly, the planet is exerting a force on the nebula. It can't be the Weak or Strong at this distance, and the nebula isn't charged, so that leaves only gravity.

Questions that would need explaining if 'the apple doesn’t pull the earth'
How can you account for gravitational self forces? E.g. a star forms in this nebula because the gases own gravity pulls itself together, or a supernova collapses into a neutron star or black hole?
How dense does a gas, or any collection of matter, have to be before it is considered 'an object' What separates the apple as an object from the earth if it is within it's atmosphere, or better, a ball of lead sinking in the ocean, from the earth?

-Andrew

 

[plane]

plane; if you imagine the sun, the moon, and the earth all attached to each other with strings, and all pulling on there strings it might help you to understand gravity.

Just because two people are pulling there strings attached to me from different sides doesn't mean i have to go both directions simultaneously, I merely go in the direction of the net force, same with gravity.

Ok now i can see your diagram I don't understand it, mind explaining?

Had a element of trouble with the diagram so it followed by about a quarter of an hour. Can understand that the first part of your post was made without the presence of the diagram.

The explanation of the diagram makes your string theory somewhat superfluous.

With that said, I can understand that no-one wants to debate a diagram that expressly says the third element of Newton’s law of gravity (every mass attracting every other mass) is wrong. That is why I just ask why people believe this to be true so as I can get a feel for why people believe what they do and get to the bottom of where everyone is at. Like no-one is born believing an apple attracts the earth. There has to be a moment in life when you decide it’s true, I’m just trying to find out what these moments are. I don’t think that is a rude thing to do. If people have beliefs, they should feel comfortable explaining the origin of their beliefs.

The diagram.

Take the two masses two represent to adjacent celestial bodies. The earth and the moon if like but not necessarily. At all times and at all earth moon separations there is point along the axis between the earth and moon centres where the resultant rate of acceleration due gravity is zero.

Once you have found any resultant zero rate of acceleration you have disproved the universal aspect of Newton’s law of gravity. That’s the key point that no-one likes much.


Newton presumed that each gravity is an indefinite extension that is uninterrupted by any other gravity. As soon as you recognize that adjacent gravities must have a zero rate of acceleration between them, you are doing a mathematical analysis that undoes Newton’s premise of all gravities being infinite extensions. You then know he was wrong about an apple attracting the earth.

To make Newton right you have to manufacture an explanation of how a rate of acceleration due to gravity either physically or mathematically rebuilds its self beyond the zero point. Think such defies rational physical and mathematical logic but anyway some might like to try and explain how gravity does its rebuild from zero.

In the case of the larger field, you can mathematically see it exists on the other side of the smaller gravity field. Not marked on the diagram but on the other side there will be an equal and equal point. So you can see the larger mass exerts a force on the smaller gravity field, but not necessarily the smaller mass.

The reason the gravity field of the smaller mass is egg shaped is the decrease of the rate of acceleration due to the larger mass between the equal and opposite point and the equal and equal point.

Of course that isn’t the end of the explanation but you can see that your strings are at odds with the zero rate of acceleration due to gravity that is in between adjacent celestial bodies.

Reply to others later.

 

[andbna]

To make Newton right you have to manufacture an explanation of how a rate of acceleration due to gravity either physically or mathematically rebuilds its self beyond the zero point. Think such defies rational physical and mathematical logic but anyway some might like to try and explain how gravity does its rebuild from zero.

Simple; the forces of gravity never becomes 0, only the net force, and therefore acceleration. However, there is no mathmatical rule which states that because
z=x+y
and z=0, that x and y=0.
indeed, all that can be derived is that x=-y, or in terms of this application (z=net force x is gravity on apple byearth, y is gravity on apple by moon,) that there is a force of gravity of equal magnitude but in opposite direction also acting upon the object. The magnitude of either force of gravity is never 0, just as Newton predicted.
Your assumption that: if z=0, and z=x+y, x MUST = y MUST=0, is the source of mathmatical error.

-Andrew