What the f*ck is up with gravity

ríomhaire

ríomhaire

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I've been wracking my brain but I must not have enough information. Gravity doesn't make sence to me. If gravity causes things to move then in creates kinetic energy, but you can't create energy. So what? It converts potential energy into kinetic? But then all things are affected by gravity so do all things just have potention energy? An infonate supply? Potention energy never realy sounded like real energy to me before. It always seemed to me to be a weak explaination of how things can be moved by gravity so I'm back to square 1 :sleep:

Please someone explain!
 
Potential energy exists. Wind up a coil, and that's potential energy until you release it.

Technically, any object moved away from the local gravititional mass gains potential energy. If you could make the mass of the Earth disappear, but the gravitational force remain, every object would go flying towards the gravitation centre.
The problem you seem to be having is one of relativity. If you take a small rock and lay it on the ground, it appears to have no potential energy at all, because the datum point from your perspective is the ground. In actuality, it has plenty of potential energy - there just isn't much scope for releasing it.
 
Pi Mu Rho said:
Potential energy exists. Wind up a coil, and that's potential energy until you release it.

Technically, any object moved away from the local gravititional mass gains potential energy.
Click to expand...
But how if energy cannot be created or destroyed?

Pi Mu Rho said:
If you could make the mass of the Earth disappear, but the gravitational force remain, every object would go flying towards the gravitation centre.
The problem you seem to be having is one of relativity. If you take a small rock and lay it on the ground, it appears to have no potential energy at all, because the datum point from your perspective is the ground. In actuality, it has plenty of potential energy - there just isn't much scope for releasing it.
Click to expand...
But what happens if something runs out of potential energy?
 
Ok, let's assume that the datum (in this case, the ground) is where an object has zero potential energy. If you pick up a small rock and place it on a table 3 foot of fhte ground, you have transferred kinetic energy into that rock, giving it the potential energy. Nudge it gently off the edge of the table, and that potential energy is converted back into kinetic.

You can't run out of potential energy - it's lossless storage :p
 
The theoretical limit (completely 0) of gravitational potential energy would be if everything were jammed into a dimensionless black hole. But there are other forces with different fall off rates that would prevent that.
 
SimonomiS said:
What's up with gravity?

No idea, but I'm down with that.
Click to expand...

This question has been pulling on me for some time...
 
OvA said:
This question has been pulling on me for some time...
Click to expand...
I don't think you understand the weight of the situation...
 
A pressing issue indeed.

My physics studying friend at college told me the other day...'gravity it not a force as every force has a counter-acting force, and gravity does not' Well i think thats what he said, and it makes sense i think, so thats another dimension to the confusion.
 
This question about gravity has tied me down.

Lame.

**** it, that sucks.
 
Hectic Glenn said:
A pressing issue indeed.

My physics studying friend at college told me the other day...'gravity it not a force as every force has a counter-acting force, and gravity does not' Well i think thats what he said, and it makes sense i think, so thats another dimension to the confusion.
Click to expand...

He's wrong. The Earth pulls you with the same force that you pull it.
 
So gravity is like a catalist that converts potential into kinetic energy?
 
ríomhaire said:
So gravity is like a catalist that converts potential into kinetic energy?
Click to expand...

Not always. Forces don't imply motion. Also, it's only the potential energy in relation to the object that's exerting the gravitational force.
 
Wait i thought gravity just warped space,and that it didn't create, convert, nor release energy.
 
Grey Fox said:
Wait i thought gravity just warped space,and that it didn't create, convert, nor release energy.
Click to expand...

Yeah, if you want to get really technical, it's actually another dimension (I think). But in practical terms it acts like a force in 4D space time.
 
Nat Turner said:
Not always. Forces don't imply motion. Also, it's only the potential energy in relation to the object that's exerting the gravitational force.
Click to expand...
Hmm. I need to think about that(and try to interpret what it means)
 
Hold on, hold on, hold on. You guys keep talking about "potential energy." What kind? Gravitational potential energy? Electric potential energy? Elastic potential energy?

I am assuming you are talking about the conversion of gravitational potential energy to kinetic energy. Anyways, from what little physics I know, I'll try and lay this out for you.

Gravitational potential energy is always negative, provided the object in question is trapped in earth's magnetic field. When you want that object to escape the field, it has to reach a positive energy level to leave the field, but that's besides the point. Energy is the ability to do work, and work is the change in energy of an object. Note that energy can't be created or destroyed, but can change forms. So, let's say you lift a ball over your head. The energy on the ball is essentially entirely gravitational. In doing work to raise the ball over your head, the gravitational potential energy increases, going from a negative number to an even less negative number. Then, when you release the ball, the ball plumets to the grounds, converting the gravitational energy to kinetic energy. The instant before the ball touches the ground, its energy is entirely kinetic and no gravitational (sorta....) is present.

Ugh...I am not sure if that answered anything, at all, but ask if you need more.

EDIT: After reading your post again, I got a few more answers.

So, no object has an infinite amount of energy present. If you really want to get complicated you can say that mass is energy and energy is mass, albeit in different forms, according to Einstein. Considering E=mc^2, you can see m is directly proportional to E, which is energy. So very little mass can have unreal amounts of energy. Now, I don't know too much about that, so you are on your own if you want to find out more about that. Anyways, when considering a falling ball, keeping in mind that energy cannot be created or destroyed, the energy present in the ball over your head must be present before it hits the ground. So, then you can say the energy at point A (up top) is equal to the energy at point B (the instant before it hits the ground). If air friction was ignored, the magnitude of energy is the exact same, just in a different form.

Oh, and when you hear about some kind of potential energy, you are talking about and objects ability to do work.
 
Err I'm not sure what your asking, rhiomhair, but I can explain some things about gravity for you...

Energy from gravity is not just "created"; in fact, there is always gravatation energy because every particle of mass in the universe is attracted to every other particle of mass in the universe. This means that every object has at least a little bit of gravatational potential energy (I think...). This energy is conserved when an object is in free-fall.

For example, Lets say your cat is on top of the Eiffel tower. Right now your cat has maximum potential energy and zero kinetic energy. Now lets say your cat reaches over to scratch its ears and falls off. As your cat descends, its potential energy is decreasing at the same rate its kinetic energy is increasing. The instant it hits the ground, kinetic energy is maximum while potential energy is zero.

After impact, all this kinetic energy is converted into different types of energy, such as: sound energy (the thud when your cat hits the ground); heat energy (the ground under your cat actually rises in temperature by a few degrees); shockwave energy (I don't really know what this is really called, but if your cat was really super fat it would created a noticable shockwave on impact); and even more kinetic energy (from your cats gibs flying in various directions).

See? all energy is conserved. :smoking:
 
well start throwing cats off buildings and all you questions shall be answered.
 
This thread is very Punny.

Hehe.

Anyway, its not potential energy. Lifting it up, like Bait said, creates potential energy. While it is resting, there is no potential energy. You cannot get energy from gravity because there is NO way to harness it.

A good way to look at it:
Look at it like a spring. When the spring isn't tensed, then there isn't any energy. When its tensed, there is potential energy. When you lift something up, there is potential energy, but not when its at rest. You see what I mean?
 
Considering we dont actually know what energy is and we happen to consider 'energy' only in 3D when it clearly isnt just that.. yes it is very funny :P.

We consider energy as the rate of doing work, but in nature that isnt the case, energy is potential ( a scalar/ virtual value) that is real to us in the form of the 3dimensional universe, existance of matter.. gravity, EM , etc.

Nature doesnt actually obey 3D conservation as we may do under present theory's application.. when we need to burn fuel for work etc. Nature uses higher symmetry conservation , to be accurate it works under conservation within 5 dimensional geometry, and that system is a giant neg entropy operation! that is the supersystem, we are presently using a macrocosm of it.

Under certain condition's there are a few experiment's which prove that this fundemental 'virtual' potential can have directly influencing real 3 dimensional effects, allowing conversion into work from a more fundemtal energy level.

the main two are..

Aharonov Bohm effect

Casimir effect
 
clarky003 said:
Nature uses higher symmetry conservation , to be accurate it works under conservation within 5 dimensional geometry
Click to expand...
:eek::eek::eek::eek::eek::eek:
 
Nature uses higher symmetry conservation , to be accurate it works under conservation within 5 dimensional geometry, Dang clarky003, Are you and
VictomofScience brothers or somthing lol
 
Haha. Gravity. Okay, I stole this image from my calvin and hobbes thread.

calvin38et.jpg









As a kid, I used to always imigine what if gravity was reversed. Walking upside down on my ceiling, stepping out of the door and trying to find some way not to fall into space.
 
It would be cool have no gravity, Untill you go outside. When I went to a space thing they have this room where they can turn the gravity off, I went in there and was just floating around for about 15 min, Was really awsome
 
Tetrahedronal pyramids are the answer to grasp the power of 'free energy' to harness anti-gravity and teleportation.

The ancients used it.:|
 
ailevation said:
Tetrahedronal pyramids are the answer to grasp the power of 'free energy' to harness anti-gravity and teleportation.

The ancients used it.:|
Click to expand...

Yeh well look how the ancients lived lol
 
And they would pull someones brain out through their nose and then wrap them up in wrap!
 
clarky003 said:
Nature doesnt actually obey 3D conservation as we may do under present theory's application.. when we need to burn fuel for work etc. Nature uses higher symmetry conservation , to be accurate it works under conservation within 5 dimensional geometry, and that system is a giant neg entropy operation! that is the supersystem, we are presently using a macrocosm of it.
Click to expand...

Universe is composed of opposite
hemispheres and opposite sexes -
equating to + / -, a zero existence,
depicted by Pyramid's bare coffer.
Your 1Day God Makes You Evil.
4 Corner Days Are Absolute, but
ignored by stupid/evil educators.
Until cornered, word is fictitious.
God is product of fictitious word.
4Day Cube Disproves 1Day God

Time Cube ftw
 
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