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#6410 04/03/06 02:39 PM
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Please explain on an atomic level why a ball rolling down a straight slope will accelerate. If you can't explain that, then explain why a ball dropped from a plane will accelerate as it falls.

And yes I have done reasearch, all I get is formulas and practical uses, but no explanation of why acceleration occurs in the first place.

.
#6411 04/03/06 06:01 PM
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A center of mass is acted upon by external force (inertial acceleration) or pursues a minimal action geodesic path through space (gravitational acceleration). Why is any of this a mystery?

A center of mass is zero dimensional. That is smaller than atomic.

Linear acceleration is rather boring. Angular acceleration is much sexier. You don't see vigorous tap dancing like Mach's Principle or frame dragging decorating linear acceleration.

Physics is about "how." Religion is about "why." If you want a working flush toilet, empirical observation suggests "how" is a much shorter and more fruitful path than "why." Vatican toilets are the products of engineers not priests. Test of faith!


Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz3.pdf
#6412 04/03/06 08:19 PM
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Feynman Lectures on Physics (vol I). This Nobel prize-winner says there is no mechanism for gravity.

I'm sure progress has been made and maybe there is a good idea now. (Wheeler's book on gravitation, which I haven't read, might be a place to start. It's called simply "Gravitation.")

For gravitation or for electricity there is a force that causes the acceleration (change of velocity). It may be that there is no better explanation than the math, but for some of us that's real enough.

#6413 04/04/06 05:25 AM
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Quote:
Originally posted by Uncle Al:
A center of mass is acted upon by external force (inertial acceleration) or pursues a minimal action geodesic path through space (gravitational acceleration). Why is any of this a mystery?

A center of mass is zero dimensional. That is smaller than atomic.
To be a bit more precice

1) The center of mass is not acted upon by anything. It is a mathematical construct to make simple mechanics easy. In the case of gravity, the force acts upon each particle with mass in an object. One can pretend that all the mass is located in the center of gravity (see 2) for drawing a free body diagram and doing freshman physics. But, just because you believe in something doesn't mean that your faith in it is well founded.

2) to be more precice than is normally necessary, you may want to refer to center of gravity to include the case where the force of gravity varies over the dimension of the object being studied.

#6414 04/04/06 11:57 PM
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You can also use Conservation of Energy . The ball rolling down the slope is losing potential energy and therefore its kinetic energy has to increase.

#6415 04/20/06 07:43 PM
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(1) acceleration is caused by an external force.
(2) the external force you are questioning is gravity...( the earths gravity in both senarios ).
(3) gravity cannot be explained on an atomic level because gravity has no mass ---> no atoms.
(4) the earths gravity is due to its mass.
(5) molecules attract each other because of their mass.
(6) a single molecule has gravity that will attract other molecules , think of the earth as a mass of molecules attracting other molecules.


hope this helps.


3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
#6416 04/20/06 10:33 PM
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paul wrote:
"(3) gravity cannot be explained on an atomic level because gravity has no mass ---> no atoms."

Not correct. Gravity has gravity. The mass of the earth is greater than the mass the earth would have were it not for gravity.

"(4) the earths gravity is due to its mass."

Only partly true. The mass of the earth is primarily the result of its mass: Not all of it.

"(5) molecules attract each other because of their mass."

Not at all true. The attraction of molecules has essentially nothing to do with their mass. Have you heard of electrons?

"(6) a single molecule has gravity that will attract other molecules...."

True only in the same sense that one could say that wind can be created by the flight of a butterfly.


DA Morgan
#6417 04/21/06 05:50 PM
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DA wrote...
Not correct. Gravity has gravity.
--> then send me a specimen of gravity so that I can observe it through a microscope please.
DA wrote...
The mass of the earth is greater than the mass the earth would have were it not for gravity.
--> gravity is just a word we use to describe an effect , it has no mass , no physical properties , it does not exist.
could you go get a pound of gravity off the shelf please?
DA wrote...
Only partly true. The mass of the earth is primarily the result of its mass: Not all of it.
--> I think there must have been a typo here so I will leave this one alone.
DA wrote...
Not at all true. The attraction of molecules has essentially nothing to do with their mass. Have you heard of electrons?
--> If you were to pour out a globe of water inside the iss in near zero gravity and then charge its north pole positive and its south pole negative would the globe separate into two globes?
or would the globes gravity keep the globe intact?
DA wrote...
True only in the same sense that one could say that wind can be created by the flight of a butterfly.
-->if it were not for the earths gravity you could hold two marbles in your hand and they would try to become one mass.
they would join together due to their gravity.

electrons are the little things that orbit atoms.
they do have charges and when these charges change they change their orbit.
the orbital change is due to the gravity of the center of the atom.
the electrons lose energy by some means which slows their orbit , naturally if the orbit slows
the centrifugal force due to the angular velocity of the electron becomes weaker then the atoms center of gravity can easily pull the electron closer to the center of its mass.

electrons of atoms can be slowed to almost no movement at all and this is how scientist have been able to almost reach zero kelvin , by draining energy from mass.

gravity is just another word.
its like time , it really isnt there...


3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
#6418 04/21/06 06:15 PM
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and another thing...
the discussion was about...

Please explain on an atomic level why a ball rolling down a straight slope will accelerate. If you can't explain that, then explain why a ball dropped from a plane will accelerate as it falls.
(1) atomic reference dropped.

(2)why a ball rolling down a straight slope will accelerate.

--> a negatively or positively charged ball would still roll down the slope. due to gravity , not its charge.

(3)then explain why a ball dropped from a plane will accelerate as it falls.

--> a negatively or positively charged ball would still fall from a plane. due to gravity , not its charge.

if you remove the force of gravity then you could float a frog for around $50,000.00 or so and your grandmother for apx $250,000.00

like they did in japan.


3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
#6419 04/21/06 09:45 PM
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Paul wrote:
"--> then send me a specimen of gravity so that I can observe it through a microscope please."

It would be far more valuable if I sent you a synapse. Do neutrinos exist? Send me one!

You lack of understanding of basic physics principles. Coupled with a lack of imagination mature enough to make you go to google.com to see if I was right puts you right there on the evolutionary scale with most other primates.

Let me show you how hard it is to educate oneself when one is not lazy. Went to google.com. Put in the search criterion "gravity has gravity." Given that I don't believe in spoon feeding except with infants ... so if you wish to eat from the tree of knowledge you are going to have to come to the table.


DA Morgan
#6420 04/22/06 03:47 AM
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no thanks DA
Im not that hungry if the food your serving is tainted.

but I suppose that if it is found on google then you are correct ... right?

if I read somewhere on google that the earth is
really flat then does that mean that it is flat?

in fact the earth was flat a long time ago
according to those who knew everything back then...

it would seem that you were called for supper and sat down at the table a little late when only the scraps were left to eat.

if you think that the food from the tree of knowledge can be found on google then that alone tells me that you went to bed hungry.

knowledge can be found on google but nonsense can also be found there , of course it is knowledge that determins which one you choose.

I have followed a few of your bickerings with others and became uninterested to say the least.
it almost seems that you want to win even if your wrong.

I do not want to continue this scrapping for ten more pages or so until one of us gives in.

so here have it your way.

gravity has gravity
and that has gravity and gravity has more gravity and more gravity and more and more and more and then gravity begins to have grandchildren gravities and then we follow on down into the generations of gravity until we come to the part where gravity begins to have mass because there is so much gravity...


3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
#6421 04/23/06 04:15 AM
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Paul wrote:
"Im not that hungry if the food your serving is tainted. but I suppose that if it is found on google then you are correct ... right?"

Wilfull ignorance doesn't wear well. Those with brains, and that use them, find that google.com takes them to Princeton University. Harvard, Cambridge, Oxford, UC Berkeley, Stanford. But I guess if you are used to the trailer park mentality you just eat whatever is served up to you.

I understand a substantial amount of the oxygen inhaled is used by the brain which converts it to CO2. Thanks for helping fight global warming.


DA Morgan
#6422 04/24/06 07:49 PM
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Robert Miller questions:

?Please explain on an atomic level why a ball rolling down a straight slope will accelerate. If you can't explain that, then explain why a ball dropped from a plane will accelerate as it falls.?

I will avoid demonstrating my lack of understanding how things work at the atomic level. Also I do not have the faintest idea why that would be relevant to the issue.

The majority opinion tells us that in a vacuum stuff attracts other stuff. An object falling to Earth has been measured accelerating at 32.61 feet per second, per second, etc. Mr. Miller wants to know why doesn?t the object stay uniform at just the first 32.61 feet per second all the way down. The first issue is why does it fall at all and the majority will blame gravity for the feat. That is only enough to get the fall started and does not, of itself, tell us why the object speeds up continually until contact.

My most likely unpopular opinion will first explain why the ball on the inclined slope continues to gain momentum and my answer is that in the instance of the Earth?s effect it is the rotation of the Earth that causes the Earth?s gravitational force to drag the object faster and faster. When you reject that idea as blasphemy then you may also want to denounce the possibility that the same rotation contributes to the straight fall object. When inertia is overcome by a contributing force the removal of the preexisting inertia has an accelerating effect on the object.

That explanation should be found objectionable enough for the clan.
jjw

#6423 04/24/06 09:41 PM
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I guess you were right DA MORGAN

now I understand how acceleration works!!
(1) its the initial gravity that initialy begins the acceleration.
(2) then its the additional "gravity has gravity" that further accelerates.
(3) and then those two gravities combine forming a larger force of gravity because of their greater magnatude resulting in further acceleration.
(4) and this keeps repeating etc...etc...etc.........

YOU HAVE FOUND THE REASON WHY THINGS ACCELERATE.
!!!! BRILLIANT !!!!
have we found a way to measure the speed at which an object falls using your "gravity has gravity"
nonsense.

or does your additional "gravity has gravity" gravity have any measure of gravitational forces associated with it?


3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
#6424 04/24/06 10:26 PM
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NASA has.

You, on the other hand, should go back to playing dodge ball.


DA Morgan
#6425 04/24/06 10:46 PM
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Wilfull ignorance drives me crazy so I decided to put an end to this nonsense for those who care about reality.

1. e=mc^2 a simplified version of Einstein's famous equation equates mass with energy.

2. If mass has gravity ... energy has gravity.

3. Gravity is a form of energy ... the rest of the mental activity should be simple enough for a cat do to.

But for those hard of thinking here is a link to a page where the gravitational contribution to earth's mass from its motion are calculated and discussed.

http://relativity.livingreviews.org/open?pubNo=lrr-2003-1&page=node3.html

For those hard of reading as well as thinking here is some of the relevant text:

"The main contribution to the gravitational potential arises from the mass of the earth; the centripetal potential correction is about 500 times smaller, and the quadrupole correction is about 2000 times smaller."

As this article is about GPSs the contribution caused by gravity, itself, is not discussed as it is too small to matter.

Since I don't believe in spoon feeding ... those interested in finding papers that discuss the contribution to earth's mass caused by its gravitational field should look up "Gravity Probe B" and "University of Washington" where I teach. Yes the work was done here.


DA Morgan
#6426 04/25/06 10:45 AM
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gravity is what we call the force exerted by one atom on all other atoms. in theory, the atoms of your body are pulling on the atoms of the farthest galaxy. with the understand of the principle of a force being exerted is the square root of the distance, we can of course see that your not having much affect. the effect is acculative. meaning that when all the atoms of the earth exert the force on the ball, the ball is pulled towards the earth and the earth is pulled towards the ball by 32 feet per second. due to its considerable more mass the earths enertia does not allow it to move much, but the ball moves easily.

this force is applied constantly, meaning that its not actually happening in seconds and foot, but in millseconds and micro inches and smaller. in each of those measurement, the enertia of the object has been affected, so in the next measure, the object is already affected, and is affected anew.


the more man learns, the more he realises, he really does not know anything.
#6427 04/25/06 05:01 PM
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dehammer wrote:
"gravity is what we call the force exerted by one atom on all other atoms."

It is not. Gravity has nothing to do with atoms. Why is it so hard for you to grasp simple concepts.

Instead of pointificating on what you don't understand try something new. Try finding out what gravity actually is.


DA Morgan
#6428 04/25/06 05:55 PM
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It seems that complex answers to questions that are fairly simple works well for some people.

I did not elaborate before but there is a very commonplace and universal thing about gravitation. The planets nearest the Sun revolve faster than those planets farther away. The same is true for all orbiting objects such as our realtionship with the Moon. If we have an object in orbit and wish to slow it down for some reason we need only move it a ways to a larger orbit.

The issue can be approached as I offered in another topic. We must account for the speed increae of objects revolving around the Sun or a planet and my simplistic approach of denser gravitation effects "dragging" the objects in ever increasing speeds works. This is what i referred to elsewhere as the gravitational envelope that is rotating with the planet. When the object is farther away there is "slippage" and all of this has been calculated in a very simple manner my me to explain how and why the planets rotate and at what predictable equatorial velocity they will do it depending on the size of the planet and the planets distance from the Sun.

There is no need for Einstein or the University of Washington to tell us the Whats for here.

I recognise that the academics answers will be more professional and sublime as well as a lot more complex and I have no disagreement with it.
jjw

#6429 04/26/06 05:38 AM
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DA Morgan wrote:
It is not. Gravity has nothing to do with atoms. Why is it so hard for you to grasp simple concepts.

Instead of pointificating on what you don't understand try something new. Try finding out what gravity actually is.

instead of pointificating on other ppls ideas being wrong, why dont you read what they write.

with out atoms there is no gravity. so me where there is a gravity source without atoms.

that does not mean that gravity is part of the atoms, but that whatever force gravity is (its one of the 4 prime forces of the universe, along with strong nuclear, weak nuclear, and electromanetic force) it is in the atom. since no one yet knows what creats it, it might be the force that creats the atom. the point is, its a matter of chicken and the egg. wiether gravity creats the atom or the atom creats gravity or neither, its still a matter of the atom having that force with in itself. you can still say that the atoms are pulling other atoms towards its, since gravity has little effect on anything not related to atoms (and yes light and most, if not all, forms of energy are related in that they are somehow interactive).


the more man learns, the more he realises, he really does not know anything.
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