How Gravity works or doesn't work

  • 50 Replies
  • 7255 Views
How Gravity works or doesn't work
« on: October 19, 2015, 02:58:31 PM »
Theoretically can a planetary body sit in space and not move in any direction. excluding gravity pulling from other sources. If the planet is alone there would be no force to move it? Correct?
Now a second Planet much smaller in mass is placed near the first, both not moving. Gravity should pull them together.
Now imagine Planet 1 is still stationary but smaller planet number 2 moves past the planet and gravity pulls it into orbit. Planet 2 has a certain amount of kinetic energy to be moving through space. The constant pull of gravity between the two planets causes the attracting force to accelerate them towards each other but the fast moving planet number 2 has only a limited amount of kinetic energy to continue its path moving past Planet 1. if gravity is strong enough to redirect Planet 2's course then the only reasonable answer is gravity would ultimately pull them together.
Can you find any way that my thinking is flawed, revolving around the sun makes no sense.
"If you were me, then I'd be you. You can't stop me no matter who you are!" - Ace Ventura pet detective

Re: How Gravity works or doesn't work
« Reply #1 on: October 19, 2015, 03:03:59 PM »
Why would planet 2 lose kinetic energy?  There are no forces acting on it.

Re: How Gravity works or doesn't work
« Reply #2 on: October 19, 2015, 03:19:15 PM »
gravity is acting on it
"If you were me, then I'd be you. You can't stop me no matter who you are!" - Ace Ventura pet detective

Re: How Gravity works or doesn't work
« Reply #3 on: October 19, 2015, 03:25:27 PM »
Im trying to simplify and isolate the event of us moving around the sun without taking in the calculations of everything else in the universe which myself and seemingly everyone on this site is un-qualified to make(not astrophysicists). By using the theory of gravity and simple logic when a spacecraft leaves earth it is in direct contrast with the pull of gravity. So it is constantly using kinetic energy to escape the pull. My question where does earth get this "fuel tank" of energy to keep moving when it is being pulled on.
"If you were me, then I'd be you. You can't stop me no matter who you are!" - Ace Ventura pet detective

Re: How Gravity works or doesn't work
« Reply #4 on: October 19, 2015, 03:27:25 PM »
Gravity isn't a force.  An object in orbit is in free fall and has no forces acting on it.

Re: How Gravity works or doesn't work
« Reply #5 on: October 19, 2015, 03:33:49 PM »
??????? jump off the ground and see if you come back down. what causes the loss of kinetic energy? friction which requires gravity to calculate? or would you come to a a stop and not come back down???? please explain i am perplexed by your answer.
"If you were me, then I'd be you. You can't stop me no matter who you are!" - Ace Ventura pet detective

Re: How Gravity works or doesn't work
« Reply #6 on: October 19, 2015, 03:49:21 PM »
Yes, you come back down.  Gravitation is caused by distortions/curvatures in space time due to mass.  When you jump, you impart a force on the Earth, causing you to leave the surface of the Earth.  However, other than air resistance, there are no other forces acting on you.  The surface of the Earth accelerates up to you due to these distortions.  This is based on the General Theory of Relativity by Einstein.  Newton's laws of gravity are a bit outdated and are not actually what is happening, but you can still use them to calculate simple things like how long will it take to land if you jump out off a building.  Newton's theory falls apart when dealing with speeds near the speed of light and in strong gravitation.  For example, there were discrepancies in Mercury's orbit using Newton's theory, Einstein's theory reconciles that.

Re: How Gravity works or doesn't work
« Reply #7 on: October 19, 2015, 04:05:21 PM »
let me get this straight, time and space are woven in a fabric. this fabric then is then extended in only a 2 dimension direction not up and down? pull a fabric tight and put some pool balls on it. they all will gravitate towards each other at the center of the fabric but yet the universe doesn't work this way. It still doesn't make sense to me.
"If you were me, then I'd be you. You can't stop me no matter who you are!" - Ace Ventura pet detective

Re: How Gravity works or doesn't work
« Reply #8 on: October 19, 2015, 04:30:41 PM »
let me get this straight, time and space are woven in a fabric. this fabric then is then extended in only a 2 dimension direction not up and down? pull a fabric tight and put some pool balls on it. they all will gravitate towards each other at the center of the fabric but yet the universe doesn't work this way. It still doesn't make sense to me.

No, it is in 3 dimensions (technically 4 with time).  Yeah, it is hard to visualize.  Here's a way to think about it, ever seen the flight path of a long flight on a flat map?  It isn't straight, it curves towards the pole.  Now look at the flight path on a curved map (globe), the flight path is now straight.

Re: How Gravity works or doesn't work
« Reply #9 on: October 19, 2015, 04:52:14 PM »
Are you familiar with the story THE EMPEROR'S NEW CLOTHES? Is it easier to believe that your wearing clothes when you look down and see your naked or is it easier to believe you are actually naked? I find the simplest answer Usually is the right one.
"If you were me, then I'd be you. You can't stop me no matter who you are!" - Ace Ventura pet detective

Re: How Gravity works or doesn't work
« Reply #10 on: October 19, 2015, 04:56:58 PM »
Okay, but Einstein was smarter than both of us, so I will trust him.

Re: How Gravity works or doesn't work
« Reply #11 on: October 19, 2015, 05:00:50 PM »
If you prefer Newtonian mechanics (which is simpler to understand) to explain why an orbiting object doesn't fall into the object it is orbiting, you will need to introduce the two fictitious forces of gravity and centrifugal force.
« Last Edit: October 19, 2015, 05:02:22 PM by TexasH »

Re: How Gravity works or doesn't work
« Reply #12 on: October 19, 2015, 05:06:47 PM »
Einstein isn't smarter than either of us He was creative and loved  theorizing. Using IMAGINATION, he created a theory. Some of his work has been disproved by others, hes man, hes fallible and flawed like us all. If you are to trust anyone TRUST YOURSELF.
"If you were me, then I'd be you. You can't stop me no matter who you are!" - Ace Ventura pet detective

Re: How Gravity works or doesn't work
« Reply #13 on: October 19, 2015, 05:09:37 PM »
Einstein isn't smarter than either of us He was creative and loved  theorizing. Using IMAGINATION, he created a theory. Some of his work has been disproved by others, hes man, hes fallible and flawed like us all. If you are to trust anyone TRUST YOURSELF.

I don't know you, maybe you are smarter than him.  General relativity has not been disproved.  That is the subject here.

Re: How Gravity works or doesn't work
« Reply #14 on: October 19, 2015, 05:52:03 PM »
Think of the words GENERAL RELATIVITY. There is nothing specific about it seems more to be taking about event probability than an actual fundamental reaction on earth. GENERAL RELATIVITY can only be explained and proved once you leave earth. Since the moon landing was debunked its been shown no one has left the earth. I believe people are crafty cunning and intelligent and can word a statement, just so, to lead others down the path of thought. Truthfully I don't subscribe to either view of earth flat or round I don't know. I think anything is possible and just like EINSTEIN said,  “Imagination is more important than knowledge. For knowledge is limited to all we now know and understand, while imagination embraces the entire world, and all there ever will be to know and understand.”
"If you were me, then I'd be you. You can't stop me no matter who you are!" - Ace Ventura pet detective

Re: How Gravity works or doesn't work
« Reply #15 on: October 19, 2015, 06:20:18 PM »
Why do you need to leave Earth to prove it?  It predates space flight.  You can observe how planets and moons move from Earth to show that GR accurately predicts their motions.

Re: How Gravity works or doesn't work
« Reply #16 on: October 19, 2015, 11:31:39 PM »
Moon landing hasn't been debunked......
Never attribute to malice that which can be explained by ignorance or stupidity.

Re: How Gravity works or doesn't work
« Reply #17 on: October 19, 2015, 11:51:51 PM »
you must believe that the world trade center was brought down by Muslims too.
"If you were me, then I'd be you. You can't stop me no matter who you are!" - Ace Ventura pet detective

?

Master_Evar

  • 3381
  • Well rounded character
Re: How Gravity works or doesn't work
« Reply #18 on: October 20, 2015, 02:07:04 AM »
Delta E = W

W = Fm*D

Fm = Fg - Fc

Delta E: change in internal energy
W: Work
Fm: Resulting force vector that causes motion.
Fg: Fictitious force due to gravity.
Fc: Fictitious force due to centrifugal effect.

If the smaller planet is in a perfectly stable orbit, then Fg = Fc and therefore
Fm = 0 and therefore W = 0, and so therefore Delta E = 0, and so therefore no energy is lost or gained.

If Fg > Fc, then the object will loose potential energy Ep but gain kinetic energy Ek. As it gains kinetic energy, the centrifugal force increases and eventually Fg < Fc, and so the planet gains Ep but looses Ek. As kinetic energy goes down, gravitational force wins again and so this cycle continues.
Math is the language of the universe.

The inability to explain something is not proof of something else.

We don't speak for reality - we only observe it. An observation can have any cause, but it is still no more than just an observation.

When in doubt; sources!

Re: How Gravity works or doesn't work
« Reply #19 on: October 20, 2015, 03:10:43 AM »
you must believe that the world trade center was brought down by Muslims too.

Are you Heiwas love child?

All evidence shows that yes it was brought down by Muslim terrorists.
Never attribute to malice that which can be explained by ignorance or stupidity.

?

Jadyyn

  • 1533
Re: How Gravity works or doesn't work
« Reply #20 on: October 20, 2015, 07:48:48 AM »
you must believe that the world trade center was brought down by Muslims too.

Are you Heiwas love child?

All evidence shows that yes it was brought down by Muslim terrorists.
Before you can say who did it, you must know what was done and how it was done. I guarantee you that most people don't know half of the effects that happened that day (I looked into it a lot and I was still surprised). I strongly suggest you get a copy of "Where did the towers go?" by Judy Wood - especially before beginning to lay blame on anyone.
“If you can't dazzle them with brilliance, baffle them with bullshit.” W.C. Fields.
"The amount of energy necessary to refute bullshit is an order of magnitude bigger than to produce it."
"What can be asserted without evidence can be dismissed without evidence."

?

Jadyyn

  • 1533
Re: How Gravity works or doesn't work
« Reply #21 on: October 20, 2015, 08:07:43 AM »
Acceleration - that is the key. An object will continue to go at the same velocity (can equal zero for a stationary object) until it is accelerated somehow. It will then go faster, slower, left, right, up or down more than it is going originally. We measure this often with some sort of scale (i.e. weight). This can be caused by accelerated linear motion (elevator going up/down), rotation (centrifuge), or pull of one object to another (unknown). The debate over what CAUSES this acceleration between objects continues. Is it intrinsic to matter (protons, neutrons, electrons) or caused by a particle (graviton) or space/time warp around matter, or what?...

The resultant velocity (where it is going) and distance (where it is) is a vector sum of the velocity and acceleration components. Depending on these, the first object may join/crash into the second (meteor), or orbit around the second (Moon/Earth or planets/Sun), or escape the second (light past the Sun/Moon).

So I am not sure what the OP question is...
“If you can't dazzle them with brilliance, baffle them with bullshit.” W.C. Fields.
"The amount of energy necessary to refute bullshit is an order of magnitude bigger than to produce it."
"What can be asserted without evidence can be dismissed without evidence."

Re: How Gravity works or doesn't work
« Reply #22 on: October 20, 2015, 10:30:48 PM »
All the physical "evidence" aside like how reporters from CNN could getting a interview from bin laden before the bombing, at his "top secret" hideout and FBI and CIA couldn't find him. Or the fact that USA military moved into Iraq for no reason other than to get the oil. Then Afghanistan, surprising. No that's what money does to people it makes them stupid. A massive Lithium mine is "discovered" in Afghanistan then suddenly hybrid cars which use Lithium Ion Batteries are available for everyone in Europe and North America, DUH. America runs of WAR, wake up. 

Watch this video about the Two Towers and the movie series BACK TO THE FUTURE. very compelling.
" class="bbc_link" target="_blank" rel="noopener noreferrer">
"If you were me, then I'd be you. You can't stop me no matter who you are!" - Ace Ventura pet detective

Re: How Gravity works or doesn't work
« Reply #23 on: October 21, 2015, 01:17:29 AM »
you must believe that the world trade center was brought down by Muslims too.

Are you Heiwas love child?

All evidence shows that yes it was brought down by Muslim terrorists.
Before you can say who did it, you must know what was done and how it was done. I guarantee you that most people don't know half of the effects that happened that day (I looked into it a lot and I was still surprised). I strongly suggest you get a copy of "Where did the towers go?" by Judy Wood - especially before beginning to lay blame on anyone.
Judy Wood and her imaginary energy weapons?  That Judy Wood?
Quote from: mikeman7918
a single photon can pass through two sluts

Quote from: Chicken Fried Clucker
if Donald Trump stuck his penis in me after trying on clothes I would have that date and time burned in my head.

Re: How Gravity works or doesn't work
« Reply #24 on: October 21, 2015, 01:52:22 AM »
Watch this video about the Two Towers and the movie series BACK TO THE FUTURE. very compelling.
" class="bbc_link" target="_blank" rel="noopener noreferrer">
"If you were me, then I'd be you. You can't stop me no matter who you are!" - Ace Ventura pet detective

Re: How Gravity works or doesn't work
« Reply #25 on: October 21, 2015, 08:09:46 AM »
Watch this video about the Two Towers and the movie series BACK TO THE FUTURE. very compelling.
<url>

Hey! Speaking of Back to the Future, today's the day!!



"Watch this video..." nah.  "very compelling." BttF was entertaining, but hardly compelling. Is there something I missed?

Where are the hoverboards?
"Everyone is entitled to his own opinion, but not to his own facts." - Daniel Patrick Moynihan

Re: How Gravity works or doesn't work
« Reply #26 on: October 21, 2015, 10:35:32 AM »
Watch this video about the Two Towers and the movie series BACK TO THE FUTURE. very compelling.
" class="bbc_link" target="_blank" rel="noopener noreferrer">
lol
Quote from: mikeman7918
a single photon can pass through two sluts

Quote from: Chicken Fried Clucker
if Donald Trump stuck his penis in me after trying on clothes I would have that date and time burned in my head.

Re: How Gravity works or doesn't work
« Reply #27 on: October 21, 2015, 11:25:48 AM »
I assume, Alpha2Omega, that you know what symbology is. If you don't even entertain the idea that the government is built off deceit, how could you understand? I apologize, this seemed quite obvious to me, but then again I haven't become institutionalized and need everything spelled out for me.
"If you were me, then I'd be you. You can't stop me no matter who you are!" - Ace Ventura pet detective

Re: How Gravity works or doesn't work
« Reply #28 on: October 21, 2015, 01:36:15 PM »
I assume, Alpha2Omega, that you know what symbology is.

Yes, but did you mean symbolism? At any rate, yes to that, too. Do you?

Quote
If you don't even entertain the idea that the government is built off deceit, how could you understand?

I understand that not everything said or done by governments is deceitful. Do you really think otherwise? If so, too bad; that makes for kind of a sucky life. Why don't you get out from behind your computer screen and do something about it if you really believe this.

Quote
I apologize, this seemed quite obvious to me, but then again I haven't become institutionalized and need everything spelled out for me.

Hey, no problem, dude! A lot of things that seem obvious to some people are just plain wrong, so you're not alone. I hope you get better soon.
"Everyone is entitled to his own opinion, but not to his own facts." - Daniel Patrick Moynihan

*

mikeman7918

  • 5431
  • Round Earther
Re: How Gravity works or doesn't work
« Reply #29 on: October 21, 2015, 03:21:16 PM »
Theoretically can a planetary body sit in space and not move in any direction. excluding gravity pulling from other sources. If the planet is alone there would be no force to move it? Correct?
Now a second Planet much smaller in mass is placed near the first, both not moving. Gravity should pull them together.
Now imagine Planet 1 is still stationary but smaller planet number 2 moves past the planet and gravity pulls it into orbit. Planet 2 has a certain amount of kinetic energy to be moving through space. The constant pull of gravity between the two planets causes the attracting force to accelerate them towards each other but the fast moving planet number 2 has only a limited amount of kinetic energy to continue its path moving past Planet 1. if gravity is strong enough to redirect Planet 2's course then the only reasonable answer is gravity would ultimately pull them together.
Can you find any way that my thinking is flawed, revolving around the sun makes no sense.

One way to think about it is that the planets are co-orbiting each other.  They would both apear to orbit a common center of mass.  Even the Earth and Moon do this, the common center of mass is a point roughly 2/3 of the way to Earth's surface from the core.

If planet 2 were moving and planet 1 was stationary then the system as a whole would start moving in the direction that planet 2 was moving at the start, if you change your frame of reference to be relative to the center of mass of the system then both planets are moving in opposite directions at all times.  When only 2 bodies are involved then they will both trace ellipses around the common center of mass, always opposite of each other and each with the same orbital period.  If you add a planet 3 though the system stops being stable and things will start colliding and/or flying apart.  if planet 3 were orbiting really far from planet 1 and planet 2 were orbiting close to planet 1 then the gravitational interaction between planets 2 and 3 would be minimal, restoring stablilty.  Another posability is if planet 3 were shrunken considerably and placed in orbit of planet 2, that way tidal forces from planet 1 are minimal and planet 3 can orbit planet 2 as if planet 1 weren't there.

In orbital mechanics, the only ways to ensure staility with 3 or more objects is if all objects orbiting a common gravity source have orbits that never come close to each other and that things have to be organized in a hierarchy of sorts like galaxies, stars, planets, and moons.

If you want I could link you to an orbital simulator program so you could play around with this stuff yourself.
I am having a video war with Jeranism.
See the thread about it here.