# The Naked Scientists Forum

### Author Topic: What makes an object or a medium fall to the ground?  (Read 24907 times)

#### Thebox

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##### What makes an object or a medium fall to the ground?
« on: 07/05/2015 16:04:57 »
What makes an object or a medium fall to the ground?

When an object is on the ground is it still falling?

How far can an object fall?

why does the surrounding ground of a hole in the ground not stop an object falling?

why does an object falling centrally into a hole not have a diagonal path?

« Last Edit: 07/05/2015 16:08:23 by Thebox »

#### Thebox

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##### Re: What makes an object or a medium fall to the ground?
« Reply #1 on: 07/05/2015 16:20:27 »

#### jeffreyH

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##### Re: What makes an object or a medium fall to the ground?
« Reply #2 on: 07/05/2015 16:27:21 »
What makes an object or a medium fall to the ground?

Gravity.

When an object is on the ground is it still falling?

The earth is pushing up against the object and preventing it from falling further. If ground is not solid then you will continue falling through that medium until it again becomes solid.

How far can an object fall?

Ultimately until it reaches the centre of gravity if the path is not obstructed.

why does the surrounding ground of a hole in the ground not stop an object falling?

The gravity of the mass of the whole earth is acting on the object which is cumulatively stronger than the ground in the immediate vicinity.

why does an object falling centrally into a hole not have a diagonal path?

That depends upon how far you observe it falling. For the short distances that we can observe unaided you would see little deviation.

#### Thebox

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##### Re: What makes an object or a medium fall to the ground?
« Reply #3 on: 07/05/2015 17:00:14 »
What makes an object or a medium fall to the ground?

Gravity.

When an object is on the ground is it still falling?

The earth is pushing up against the object and preventing it from falling further. If ground is not solid then you will continue falling through that medium until it again becomes solid.

How far can an object fall?

Ultimately until it reaches the centre of gravity if the path is not obstructed.

why does the surrounding ground of a hole in the ground not stop an object falling?

The gravity of the mass of the whole earth is acting on the object which is cumulatively stronger than the ground in the immediate vicinity.

why does an object falling centrally into a hole not have a diagonal path?

That depends upon how far you observe it falling. For the short distances that we can observe unaided you would see little deviation.

You say the Earth is pushing up against the object according to Newtons third Law and the Fn=0.

An object falls towards the center of gravity, centripetally, for something to push, it has to have force, so what force are you suggesting that enables the ground to push away from the center of gravity and push back at an object to an equal and opposing force to maintain Fn=0?

I suggest the ground is also centripetally being forced in the direction of the earths core and is destination bound, the same as the object to  the core, I suggest the ground has no ability to push back against an object because they are both travelling the same direction under the same force, I suggest an object is always falling but can not fall any further because of a traffic jam of matter in the way being stopped isotropically by a central point of pressure.

I suggest an earthquake pushes back,

What would your opinion be of this?

« Last Edit: 07/05/2015 17:06:15 by Thebox »

#### Colin2B

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##### Re: What makes an object or a medium fall to the ground?
« Reply #4 on: 07/05/2015 17:26:46 »
If you are going to put up your own theory, it ought to be in New Theories.
I'm not responding to your questions for reasons I've given before.

#### Thebox

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##### Re: What makes an object or a medium fall to the ground?
« Reply #5 on: 07/05/2015 17:28:18 »
If you are going to put up your own theory, it ought to be in New Theories.
I'm not responding to your questions for reasons I've given before.

it is a discussion with question marks, not a theory,what do you think?

#### David Cooper

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##### Re: What makes an object or a medium fall to the ground?
« Reply #6 on: 07/05/2015 17:43:08 »
What makes an object or a medium fall to the ground?

A medium is a special case - if he or she is in communication with someone dead at the time, he/she may float above the ground and not fall.

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When an object is on the ground is it still falling?

It's still being pulled in a downward direction, but it's now being slightly compressed by this force as it's being blocked from moving down any further. Clearly it is not falling.

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How far can an object fall?

All the way down.

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why does the surrounding ground of a hole in the ground not stop an object falling?

Because it's in the wrong place to stop an object that goes through the hole.

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why does an object falling centrally into a hole not have a diagonal path?

What is a diagonal path in this context?

Quote
I suggest the ground is also centripetally being forced in the direction of the earths core and is destination bound, the same as the object to  the core, I suggest the ground has no ability to push back against an object because they are both travelling the same direction under the same force, I suggest an object is always falling but can not fall any further because of a traffic jam of matter in the way being stopped isotropically by a central point of pressure.

Don't bring the word centripetal into this. Other than that though, you're thinking in the right direction - there's a pile up which results in a high pressure building up, and the force pushing back upwards is that pressure, but it's important to understand that the pressure is powered by inwards/downward gravity.

Quote
I suggest an earthquake pushes back,

Why would you want to bring that in here?

#### Thebox

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##### Re: What makes an object or a medium fall to the ground?
« Reply #7 on: 07/05/2015 17:59:53 »
What makes an object or a medium fall to the ground?

A medium is a special case - if he or she is in communication with someone dead at the time, he/she may float above the ground and not fall.

Quote
When an object is on the ground is it still falling?

It's still being pulled in a downward direction, but it's now being slightly compressed by this force as it's being blocked from moving down any further. Clearly it is not falling.

Quote
How far can an object fall?

All the way down.

Quote
why does the surrounding ground of a hole in the ground not stop an object falling?

Because it's in the wrong place to stop an object that goes through the hole.

Quote
why does an object falling centrally into a hole not have a diagonal path?

What is a diagonal path in this context?

Quote
I suggest the ground is also centripetally being forced in the direction of the earths core and is destination bound, the same as the object to  the core, I suggest the ground has no ability to push back against an object because they are both travelling the same direction under the same force, I suggest an object is always falling but can not fall any further because of a traffic jam of matter in the way being stopped isotropically by a central point of pressure.

Don't bring the word centripetal into this. Other than that though, you're thinking in the right direction - there's a pile up which results in a high pressure building up, and the force pushing back upwards is that pressure, but it's important to understand that the pressure is powered by inwards/downward gravity.

Quote
I suggest an earthquake pushes back,

Why would you want to bring that in here?

The diagonal path was in relationship to curvature, I mentioned earth quakes because the seismic waves from beneath force the ground to wave up and down by tectonic plate movement, I though this was in relationship to a build up of something being released, and the ground being pushed the opposite way to gravity,

I understand the earth wants to implode , but I still do not understand how it can push an object back, surely the object is pushing the ground?

And is the force you mention that pushes back , not KE and the magnetic field?

« Last Edit: 07/05/2015 18:01:40 by Thebox »

#### alancalverd

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##### Re: What makes an object or a medium fall to the ground?
« Reply #8 on: 07/05/2015 18:04:51 »
For the time being I'm prepared to accept this as a genuine question because it has a classic answer.

IIRC the time taken for an object to fall through a hole in the centre of the earth is about 42 minutes, though the figure has been revised from time to time as we learn about the inhomogeneities of the planet.

If we ignore air resistance (and why not? We are ignoring pretty much everything else we know about the earth!) and consider the planet to be a perfect sphere, the object's acceleration can be calculated at every point by subtracting the contribution of the shell above it. As it passes the centre it will slow down (there now being more mass "above" than "below") until it pops out of the hole in the Antipodes, reaches a height above ground exactly the same as the height you dropped it from, and returns whence it came.

Plenty of mathematicians and physicists have solved the equations, and it used to be part of the undergraduate general physics syllabus, but I understand that the questioner isn't particularly interested in physics or maths.

The most readable treatment of the question that I have come across, is "The Krone Experiment" - a brilliant novel by a geophysicist,  sadly turned into a crap DVD by the author's brother - in which the antihero makes a small black hole and, of course, drops it. Neat trick because of course the black hole creates its own tunnel! There are a couple of equations in the book (including corrections for rotation) but they aren't vital to the plot and there's also enough sex and violence to interest an unsophisticated mind. Enjoy and learn....

#### Thebox

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##### Re: What makes an object or a medium fall to the ground?
« Reply #9 on: 07/05/2015 18:17:14 »
For the time being I'm prepared to accept this as a genuine question because it has a classic answer.

IIRC the time taken for an object to fall through a hole in the centre of the earth is about 42 minutes, though the figure has been revised from time to time as we learn about the inhomogeneities of the planet.

If we ignore air resistance (and why not? We are ignoring pretty much everything else we know about the earth!) and consider the planet to be a perfect sphere, the object's acceleration can be calculated at every point by subtracting the contribution of the shell above it. As it passes the centre it will slow down (there now being more mass "above" than "below") until it pops out of the hole in the Antipodes, reaches a height above ground exactly the same as the height you dropped it from, and returns whence it came.

Plenty of mathematicians and physicists have solved the equations, and it used to be part of the undergraduate general physics syllabus, but I understand that the questioner isn't particularly interested in physics or maths.

The most readable treatment of the question that I have come across, is "The Krone Experiment" - a brilliant novel by a geophysicist,  sadly turned into a crap DVD by the author's brother - in which the antihero makes a small black hole and, of course, drops it. Neat trick because of course the black hole creates its own tunnel! There are a couple of equations in the book (including corrections for rotation) but they aren't vital to the plot and there's also enough sex and violence to interest an unsophisticated mind. Enjoy and learn....

Thank you for understanding that is just questions, a dropped black hole is a very interesting idea, the sex and violence irrelevant.

I will make a small analogy

If you can imagine a sphere shaped magnet, and some way dropping iron fillings isotropic onto the magnet they will form an even layer, repeat and keep repeating, at no time do the iron fillings push back?

added - the magnetic field of the earth pushes back em radiation from the sun?
« Last Edit: 07/05/2015 18:22:25 by Thebox »

#### alancalverd

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##### Re: What makes an object or a medium fall to the ground?
« Reply #10 on: 07/05/2015 18:22:31 »
A dropped black hole is just a hypothesis, and the equations are pretty trivial. Sex and violence are much more relevant to real life, completely absorbing, and way beyond understanding.

As long as you have a convergent magnetic field, iron filings will converge on it.

Quote
added - the magnetic field of the earth pushes back em radiation from the sun?
no.

#### Thebox

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##### Re: What makes an object or a medium fall to the ground?
« Reply #11 on: 07/05/2015 18:25:24 »
A dropped black hole is just a hypothesis, and the equations are pretty trivial. Sex and violence are much more relevant to real life, completely absorbing, and way beyond understanding.

As long as you have a convergent magnetic field, iron filings will converge on it.

Quote
added - the magnetic field of the earth pushes back em radiation from the sun?
no.

I  thought the Em field blocked harmful UV rays and gamma radiation , is that not an opposing and equal force?

added - and blocks the solar wind?
« Last Edit: 07/05/2015 18:27:48 by Thebox »

#### Thebox

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##### Re: What makes an object or a medium fall to the ground?
« Reply #12 on: 07/05/2015 20:40:49 »
sorry added question I just thought of,

why do clouds not fall to the ground when they have more mass than air per part?

#### chiralSPO

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##### Re: What makes an object or a medium fall to the ground?
« Reply #13 on: 07/05/2015 20:53:21 »
Clouds don't have more mass per volume that air--that's why they float. When they get dense enough they precipitate (rain, snow, etc.)

#### Thebox

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##### Re: What makes an object or a medium fall to the ground?
« Reply #14 on: 07/05/2015 21:06:27 »
Clouds don't have more mass per volume that air--that's why they float. When they get dense enough they precipitate (rain, snow, etc.)

thank you, so when a cloud gains more mass (becomes denser) before it precipitates, does the cloud sink to a lower altitude?

#### chiralSPO

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##### Re: What makes an object or a medium fall to the ground?
« Reply #15 on: 07/05/2015 21:27:16 »
I think that clouds can get lower as they get denser, but you can't really think of clouds as discrete objects, so some of the intuition that goes with objects doesn't really apply here...

#### Thebox

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##### Re: What makes an object or a medium fall to the ground?
« Reply #16 on: 07/05/2015 21:35:08 »
I think that clouds can get lower as they get denser, but you can't really think of clouds as discrete objects, so some of the intuition that goes with objects doesn't really apply here...

I know you may think clouds have gone off topic but clouds contain falling ''objects'' such as rain and hail.

Does rain or hail contain any net charge?

#### Colin2B

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##### Re: What makes an object or a medium fall to the ground?
« Reply #17 on: 07/05/2015 22:34:14 »
I think that clouds can get lower as they get denser, but you can't really think of clouds as discrete objects, so some of the intuition that goes with objects doesn't really apply here...
As you know clouds are formed by warm moist air rising due to it's buoyancy, as the air rises it will cool due to natural atmospheric cooling with height (1degC/300m for saturated air). When it hits dew point it will condense and form cloud. If a cloud did go below the dew point level the moisture would evaporate. The bottom of a cloud is continually in an in between state. All this assumes the air is stable, ie not much intermixing due to wind or air currents.
Alan will know a lot more about it, I only know mountain and surface effects.

#### alancalverd

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##### Re: What makes an object or a medium fall to the ground?
« Reply #18 on: 07/05/2015 23:22:11 »
The earth does not have a significant electromagnetic field, and even if it did, that would have no effect on radiation from the sun.

A cloud is not a "thing" but a dynamic collection of droplets of water or ice. The appearance of semipermanence is due to water evaporating at the interface with drier air, or condensing as the air cools, either as a result of expansion or radiation. The processes are quite sudden and the interfaces therefore quite sharp - there can be as little as 10 feet altitude change between clear air and "solid" fog with visibilty less than a foot.

#### Thebox

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##### Re: What makes an object or a medium fall to the ground?
« Reply #19 on: 08/05/2015 08:09:52 »
The earth does not have a significant electromagnetic field, and even if it did, that would have no effect on radiation from the sun.

A cloud is not a "thing" but a dynamic collection of droplets of water or ice. The appearance of semipermanence is due to water evaporating at the interface with drier air, or condensing as the air cools, either as a result of expansion or radiation. The processes are quite sudden and the interfaces therefore quite sharp - there can be as little as 10 feet altitude change between clear air and "solid" fog with visibilty less than a foot.

Your answer is rather confusing , anything is technically a ''thing'' , droplets of water or ice? that is certainly a thing that has mass, so why? before they ''fall'' do they stay floating, water and ice are heavier than air.

Fog interesting you should mention fog that hugs the surface, is fog a cloud at low level?  if yes, what is the difference to a cloud at altitude?

My original question was ,  What makes an object or a medium fall to the ground?

The answer given was gravity, so you should be able to tell me exactly what gravity is?  if you can not then gravity can not exist in a sense and in my opinion would be along the lines of Unicorns.

Matter only contains so much, something of matter causes gravity, so what is it?

the list is one long...I will re-phrase my question, what make an atom attract to another atom to form density?

« Last Edit: 08/05/2015 08:18:39 by Thebox »

#### Colin2B

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##### Re: What makes an object or a medium fall to the ground?
« Reply #20 on: 08/05/2015 14:37:46 »
I will answer some of these as other genuine enquirers will be watching

.........so why? before they ''fall'' do they stay floating, water and ice are heavier than air.
Water vapour is less dense than dry air and hence buoyant. This is described above. As the  vapour rises it gets colder and more moisture condenses out to start forming droplets, these often freeze because of the low temperature at altitude and being heavier start to fall. The exact physics is too complex to discuss here. As an example this paper covers air density, read at your leisure http://journals.ametsoc.org/doi/pdf/10.1175/JAS-D-11-085.1

Fog interesting you should mention fog that hugs the surface, is fog a cloud at low level?  if yes, what is the difference to a cloud at altitude?
Yes, fog is a cloud at low level. I don't understand your follow up, I've said there is no difference, so why do you expect an explanation of the non existent difference??
The only reason it stays where it is is to do with temperature eg in some circumstances the fog is trapped under an inversion layer.

My original question was ,  What makes an object or a medium fall to the ground?

"...........The answer given was gravity, so you should be able to tell me exactly what gravity is?  if you can not then gravity can not exist in a sense and in my opinion would be along the lines of Unicorns.
Why don't you stick to your original questions?

You have been given answers about gravity before, but you have your own theory. According to you we are wrong. That's ok we can live with it, move on.

the list is one long...I will re-phrase my question, what make an atom attract to another atom to form density?
This is not a rephrasing, it is a new question. Start a new thread if you genuinely want to know, or if you have your own theory put it in New Theories along with the rest of your gravity theory.

#### Thebox

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##### Re: What makes an object or a medium fall to the ground?
« Reply #21 on: 09/05/2015 09:11:15 »
I will answer some of these as other genuine enquirers will be watching

.........so why? before they ''fall'' do they stay floating, water and ice are heavier than air.
Water vapour is less dense than dry air and hence buoyant. This is described above. As the  vapour rises it gets colder and more moisture condenses out to start forming droplets, these often freeze because of the low temperature at altitude and being heavier start to fall. The exact physics is too complex to discuss here. As an example this paper covers air density, read at your leisure http://journals.ametsoc.org/doi/pdf/10.1175/JAS-D-11-085.1

Fog interesting you should mention fog that hugs the surface, is fog a cloud at low level?  if yes, what is the difference to a cloud at altitude?
Yes, fog is a cloud at low level. I don't understand your follow up, I've said there is no difference, so why do you expect an explanation of the non existent difference??
The only reason it stays where it is is to do with temperature eg in some circumstances the fog is trapped under an inversion layer.

My original question was ,  What makes an object or a medium fall to the ground?

"...........The answer given was gravity, so you should be able to tell me exactly what gravity is?  if you can not then gravity can not exist in a sense and in my opinion would be along the lines of Unicorns.
Why don't you stick to your original questions?

You have been given answers about gravity before, but you have your own theory. According to you we are wrong. That's ok we can live with it, move on.

the list is one long...I will re-phrase my question, what make an atom attract to another atom to form density?
This is not a rephrasing, it is a new question. Start a new thread if you genuinely want to know, or if you have your own theory put it in New Theories along with the rest of your gravity theory.

Thank you Colin for your answers, you think my questions are new questions, I think my questions are relevant to my fist question and a part of the question.
A fog cloud hugs the ground, clouds float, air rises and air sinks , a convection process.

The question to my question torn apart to the basics, is why does an atom attract to an atom to form density?

Clouds form to make density, so what attracts the water vapour/gas to other water vapour/gas to form density?

The water vapour/gas becomes dense then falls back to the ground, the same force of attract that holds the density together in the first place of the cloud.

My questions are on topic, most things are connected in some way , to dig deep we have to consider all aspects of the question to get an appropriate answer.

Gravity is not an answer I am looking for, I want more of an answer than just the naming of something, We could of just called gravity falling, that is the use and description on earth.

I have done a fundamental breakdown of matter, which leads me to atoms, so if the earth is atoms and clouds are atoms, rain is denser atoms and attracted to the earth what makes the atoms attracted to atoms?

I do not know, you should know, and when you tell me the answer, I then know why an object falls to the ground.

#### alancalverd

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##### Re: What makes an object or a medium fall to the ground?
« Reply #22 on: 09/05/2015 09:30:35 »

A fog cloud hugs the ground, clouds float, air rises and air sinks , a convection process.

The question to my question torn apart to the basics, is why does an atom attract to an atom to form density?

Chemistry. In the case of clouds, and water generally, read up about hydrogen bonds.

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Clouds form to make density, so what attracts the water vapour/gas to other water vapour/gas to form density?

Any system will tend to the lowest energy state. In the case of water, the free surface energy of a droplet decreases as the droplet size increases.

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The water vapour/gas becomes dense then falls back to the ground, the same force of attract that holds the density together in the first place of the cloud.

No. Gravity has nothing to do with the hydrogen bond.

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Gravity is not an answer I am looking for, I want more of an answer than just the naming of something, We could of just called gravity falling, that is the use and description on earth.
Alas, that is the name of the force that isn't electrostatic, magnetic, nuclear or anything else. You might as well ask why like charges repel, whilst insisting thet "electrostatic force" isn't an acceptable answer.

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I have done a fundamental breakdown of matter, which leads me to atoms, so if the earth is atoms and clouds are atoms, rain is denser atoms and attracted to the earth what makes the atoms attracted to atoms?

See above. But if you don't believe in electron orbitals or the fact that gravity is not electrostatic, you won't accept any answers anyway.

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I do not know, you should know, and when you tell me the answer, I then know why an object falls to the ground.

Science isn't about "why" but "how".

#### Colin2B

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##### Re: What makes an object or a medium fall to the ground?
« Reply #23 on: 09/05/2015 11:39:53 »
I agree with Alan (then we would wouldn't we - conspiracy)

You started a topic on gravity and why things fall to the ground. The question of why atoms bond to form molecules, and then molecules grouping to form elements and compounds, has nothing to do with gravity.

Because you refuse to read up on basic physics and chemistry and insist on thinking it up for yourself, our answers to your questions will never make sense to you, and you will always feel frustrated.

#### Thebox

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##### Re: What makes an object or a medium fall to the ground?
« Reply #24 on: 09/05/2015 12:11:00 »
I agree with Alan (then we would wouldn't we - conspiracy)

You started a topic on gravity and why things fall to the ground. The question of why atoms bond to form molecules, and then molecules grouping to form elements and compounds, has nothing to do with gravity.

Because you refuse to read up on basic physics and chemistry and insist on thinking it up for yourself, our answers to your questions will never make sense to you, and you will always feel frustrated.

Science says that all matter is made of atoms ? yes or no

The Cavendish experiment shows using ''balls'' that all mass is attracted to mass? yes or no

All matter has mass? yes or no

A single atom has mass? yes or no

single atoms mass are attracted to other single atoms mass? yes or no

What makes a cluster of atoms(an object) fall to the ground?

Atoms have to be attracted to atoms ,

You say an electron is a negative polarity attached to a positive polarity Proton,

So the atom emits a positive and a negative polarity at the same time? yes or no

a (+) and (-) electrostatic nuclear bond, would = +- in attract? yes or no A+B=C

It is not a theory and all relevant to my original question. Science keeps leaving me without answers, I am quoting your own facts back to you, not making random assumptions, it is your information.

« Last Edit: 09/05/2015 12:26:59 by Thebox »

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##### Re: What makes an object or a medium fall to the ground?
« Reply #24 on: 09/05/2015 12:11:00 »