Civilization Among The Other Planets

[mindphuk]

[video=youtube;8bTdMmNZm2M]http://www.youtube.com/watch?v=8bTdMmNZm2M[/video]

 

[Finshaggy]

And don't say the force is miles of rock and lava, because if it's mils of rock and lava, gravity is what pulls them down and makes that pressure. And it's stronger at the core.

 

[LightningMcGreen]

No if the force is greater here what is the force that is causing the molten lava in the core. The lower you go the stronger gravity is. Just like the further away from earth you are the less effect its hold has.

Well here's on of the articles that explains it better than l can lol

In the center of the Earth, there are equal amounts of mass in all directions at any given distance, so gravity pulls equally hard in all directions, so an object at the center of the Earth would feel zero net gravity. Such an object would be under enormous pressure, because it does feel the weight of all mass that lies on top of it.
Outside of the Earth, gravity behaves as if all mass of the Earth were concentrated in the very center point, but inside the Earth gravity does not behave like that.
Gravity comes from mass, not from a particular point. Only in the precise center is the gravity equal to zero.
This holds also in the center of a black hole, if the law of gravity as we know it is still valid there (which we don't know).
If the Earth were hollow inside, and all of its mass were in the surface shell, and the mass distribution was spherically symmetric, then you'd be weightless everywhere in the hollow space inside the Earth.
The green line in http://www.splung.com/kinematics/images/gravitation/variation%20of%20g.png shows the variation of the strength of gravity with distance from the center of the Earth. Gravity is zero in the very center, then rises fairly linearly to about 109% of the surface gravity at about 55% of the distance to the surface, then drops back to about 100% and stays there until the surface. Beyond the surface the gravity decreases with the square of the distance from the center.
The red line in the same graph shows the variation of gravity if the Earth were equally dense everywhere. Then the strength of gravity would increase linearly from 0 in the middle to 100% at the surface. That in the "real" Earth the variation of gravity is different is because the Earth is not equally dense everywhere, but is a lot denser near the middle than near the surface.

 

[cannabineer]

Actually...l've heard more than once that gravity is stronger on the surface, moreso than at the center of the earth...something about the forces of matter in the middle cancelling each other out...not saying it's true, but l've heard something along those lines multiple times

This was one of the "blackboard problems" i remember from physics class. At the earth's center of mass, the local gravitational effect is nearly zero, with the "nearly" being solar and lunar tidal offset. A body only experiences weight from the mass below it. The spherical shell above a subsurface object still exerts gravity, but it cancels out. Zero vector sum. At the center of mass, all the planet's weight is above and cancels itself out.
cheers 'neer

Addendum about which is stronger - electromagnetism or gravity. EM forces can be made to be *locally* much stronger. Over long distances however, gravity wins. A galaxy or solar system is shaped almost entirely by gravitational forces.

<edit> In the time it took me to formulate this post, I've been anticipated.

 

[Finshaggy]

But IT WOULDN'T be able to escape be cause the gravity around it would be so great. It may have 0 gravity at the exact center. But you try getting something at the center out with a magnet from a foot a way. I don't care if you've got a 40lb magnet. That paper clip isn't coming.

 

[Luger187]

Two objects in space, one a Sherman Tank and the other, myself. if I push the Sherman tank, I will move away, not the Sherman tank. Someone stated that two objects of different masses would move away at the same rate, but that is simply not true.

what did the tank see? it saw the same exact thing you did, except opposite. it saw YOU moving away from IT at the same rate you claimed to see the tank move away from you. it all depends on what your perspective is. just like the paper-earth analogy.

with two objects of different masses in space, they both move away from eachother when you push the tank. unless you have some third party object to determine speed, you cant say you are moving faster than the tank, because the tank could just as easily say it is faster than you and you are staying still. you two are simply moving apart from one another.
but if there is a third party object, you both can determine what is happening a little better, but ONLY in relation to that other object and eachother.

The object of lesser mass will move, and not the larger, each and every time. Get some rolly chairs, and a few different weighted friends, give it a try. Applies in space too.

you only see that effect because there are third party objects that both people can relate to. if the two pushed eachother in space, you cant say the smaller massed person moved and the big one didnt because you have nothing to relate that motion to except eachother.

Just because an object is the size of Jupiter, doesn't mean it has the same gravitational feild as Jupiter, it COULD not have one at all if the structure is coreless.

size is not the issue. mass is what determines gravity. why would it not have gravity without a core? if it is made of matter and has mass, it has gravity.

 

[mindphuk]

But IT WOULDN'T be able to escape be cause the gravity around it would be so great. It may have 0 gravity at the exact center. But you try getting something at the center out with a magnet from a foot a way. I don't care if you've got a 40lb magnet. That paper clip isn't coming.

May I ask where you went to school?

 

[Finshaggy]

No you can't. You've lurked me enough. Can I ask if you drink blue ribbon and won't pull the stick out of your ass?

 

[LightningMcGreen]

<edit> In the time it took me to formulate this post, I've been anticipated.

At least you're able to explain it off the top of your head...l had to google LOL

 

[cannabineer]

size is not the issue.

Whoever told you that ... she lied.

In the Sherman tank example, conservation of momentum is the thing. The tank moves; the person moves. What does not move (or change velocity/direction) is the center of mass of that two-body ensemble. But you know that. I'm just tilting at the clarity windmills. Sancho! My armor ... !!
cheers 'neer

 

[Luger187]

That is an entirely different subject, which has been said, only proves to contain forces greater than that of gravity.
That is an entirely different subject, which has been said, only proves to contain forces greater than that of gravity.
That is an entirely different subject, which has been said, only proves to contain forces greater than that of gravity.
That is an entirely different subject, which has been said, only proves to contain forces greater than that of gravity.

Of coarse a concentrated magnetic to a piece of steel will unite before they both unite with the ground, however, when you let go, they will both fall to the ground. You are only representing a tighter bond within the realm of gravity. we already KNOW that certain metals are magnetic and attract to one another. but this does not correlate with the actions of gravity.

Rub a ballon on your head and stick it on the wall, does that mean gravity is static? No, its a stronger force that isn't entirely relevant.

okay apparently you still dont get it. im not saying gravity disappears and magnetism takes over. im saying a small magnet can have enough force to attract a paperclip into the air. this means the entire earths gravity was not strong enough to hold the paperclip down against the magnetism

 

[THENUMBER1022]

anyone who tells you that every object in space has the same mass is a joke. I'm done.

Laws apply on Earth, but to say the moon has an equal mass or equal gravitational pull is wrong. Otherwise we would spin together, instead of having the smaller mass remain one-sided, always having the opposing side facing away. Clearly, we have a greater gravitational pull. All that guy did was ask a bunch of people a question and get the "wrong" answer he knew he'd receive, only so he can recite someone else's theory. That might be your definition of smart, but I differ.

Trusting laws which are evidently not accurate or relative is the Achilles heal of society. If this is about science, then I'm out. I was under the assumption this was about what we know.

 

[LightningMcGreen]

okay apparently you still dont get it. im not saying gravity disappears and magnetism takes over. im saying a small magnet can have enough force to attract a paperclip into the air. this means the entire earths gravity was not strong enough to hold the paperclip down against the magnetism

I can also overcome gravity by picking up a dime off the floor...superhuman, right here

 

[THENUMBER1022]

okay, lugar187, clearly YOU do not get it.

I, not you, was re-enforcing the fact that gravitational pull is relative to mass, but thanks for twisting my words and basically saying the exact same thing. I am saying although an object might be the size of Jupiter, it could have 1/10 the mass of jupiter(I.E. HOLLOW, CORELESS, MADE UP OF GAS)

YOU ARE NOT UNDERSTANDING that mass does in no way shape or form correlate to size.

 

[mindphuk]

anyone who tells you that every object in space has the same mass is a joke. I'm done.

Laws apply on Earth, but to say the moon has an equal mass or equal gravitational pull is wrong. Otherwise we would spin together, instead of having the smaller mass remain one-sided, always having the opposing side facing away. Clearly, we have a greater gravitational pull. All that guy did was ask a bunch of people a question and get the "wrong" answer he knew he'd receive, only so he can recite someone else's theory. That might be your definition of smart, but I differ.

Trusting laws which are evidently not accurate or relative is the Achilles heal of society. If this is about science, then I'm out. I was under the assumption this was about what we know.

[video=youtube;cP0Bb3WXJ_k]http://www.youtube.com/watch?v=cP0Bb3WXJ_k&feature=related[/video]

 

[THENUMBER1022]

OKAY, 187, I got an idea. Drop two paper clips from a plane and hold a magnet in your hand. If you catch one, let me know.

Like canibineer stated, only locally does it overpower, implying it is an irrelevant force in the actions of gravity. You can also jump out of a plane with a paper clip and magnet. Yes the magnet might find the paperclip, but they are still falling at the exact same rate as gravity. A magnet dropped will still fall towards earth.

 

[Luger187]

Whoever told you that ... she lied.

i knew it! that bitch! lol

In the Sherman tank example, conservation of momentum is the thing. The tank moves; the person moves. What does not move 9or change velocity/direction) is the center of mass of that two-body ensemble. But you know that. I'm just tilting at the clarity windmills. Sancho! My armor ... !!
cheers 'neer

okay so the force you exert 'on the tank' by pushing it is 'split' between the two objects?
and what if the two are moving away from eachother, and a third object came and bumped the tank in a different direction than where it was goin. basically the tank would move to the left or right(whichever 'way' its pushed). wouldnt this change the location of the center of mass? i think it will, but it also changes the example haha

 

[mindphuk]

No you can't. You've lurked me enough. Can I ask if you drink blue ribbon and won't pull the stick out of your ass?

You are extremely hostile to people that wanted to help you clear up misconceptions. What makes you think you are more correct about these things than the actual scientists that study them?

 

[mindphuk]

I can also overcome gravity by picking up a dime off the floor...superhuman, right here

No, it means that you are able to overcome the force of gravity on the paperclip with just your muscles. You can also pull the paperclip away from the magnet too so you might think you are stronger than magnetism. However, I can produce a magnet that you would not be able to pull it away from. At short distances, magnetism is extremely strong but does not work over distance. Even though gravity is very weak, it acts over enormous distances.

 

[THENUMBER1022]

mindphuk, isnt that exactly what I said in each post and example I provided? I claimed that a truely heavier object, in space, will move much much less than a smaller object. yes it is all relative but as far as geographical movement, and not perspective of the other object, the large object will always move less.