Another wild thought: what if you were in.....

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Famine
Did I say it would?

I said that there is no net force when two horses of equal strength pulling in opposite directions.

I wasn't using it as proof of anything other than that "no net force" doesn't necessarily equate to nothing.
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Two horses of equal force pulling in opposite directions would not cancel eachother out - they would double the effect.

Look at it like this: tie one arm to a poll and the other to a horse. You have the force of one horse pulling your arms off. But a horse on each arm is the force of two horses pulling your arms off.

Your analogy is flawed.
 
Add the vectors up.

You have a force of, say, 1500N acting in a due west direction. <---------------
You have another force of, say, 1500N acting in a due east direction. --------------->

---------------> + <--------------- = 0


Tie a rope between the two horses. What's the net effect? Do the horses go one way or the other, or neither?
 
LoudMusic
Two horses of equal force pulling in opposite directions would not cancel eachother out - they would double the effect.

Look at it like this: tie one arm to a poll and the other to a horse. You have the force of one horse pulling your arms off. But a horse on each arm is the force of two horses pulling your arms off.

Your analogy is flawed.
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Horse forces act on only some of the particles in your body, wheras gravity acts on every particle in your body. That is the flaw in Famine's analogy.
 
Which wasn't actually part of it. I was JUST saying that "No net force" (which is the same thing as "balanced forces") doesn't equal "Not dead".
 
Famine is right, there is no net force on your body as a whole. However, there is a net force to your limb that is attached to the rope, since it is a component of your whole body.
 
Famine
Add the vectors up.

You have a force of, say, 1500N acting in a due west direction. <---------------
You have another force of, say, 1500N acting in a due east direction. --------------->

---------------> + <--------------- = 0


Tie a rope between the two horses. What's the net effect? Do the horses go one way or the other, or neither?
Click to expand...

That which ties them together is not experiencing zero force.
 
Famine
You have a force of, say, 1500N acting in a due west direction. <---------------
You have another force of, say, 1500N acting in a due east direction. --------------->

---------------> + <--------------- = 0
Click to expand...

You've put it the other way around:p
<----------------:scared:ME:crazy:-------------------->=torn apart


Best thread I've had so far lol:sly:
 
Man, I love physics!

My Physics teacher gave us this same conundrum at the start of last year. He added some crucial parts:
- The tube has frictionless walls
- The tube cannont break
- There is no air in the tube aka no wind resistance
- You have a breathing aparatus (duh)

How much would that alter the problem?

He never told us the answer.
 
So beat on an indestructible toy with an indestructable toy. Yay.

You know, you can take all the physics classes you want, and use all the equations you'd like to use, but the only way to know for sure about anything is trial and error. Even NASA, with the smartest physicists in the world, get things wrong the first time (or even subsequent times after that ...).

It is my understanding that as you near the center of a mass the gravitational forces increase. With increased pressure you get increased energy. With increased energy you get increased heat. With increased heat you turn solids into liquids. Eventually it squirts to the surface as a volcano, so I figure that's mostly correct. So if something as frail as a human were to begin a journey to the center of the earth they would need something more resistant to heat and pressure than the rock itself. Personally I don't think you'd get very far before being crushed like an empty tin can under the wheel of a diesel locomotive.
 
And by frictionless, I mean lim x->0 of friction. I have heard the argument of absolutely no friction would stop anything that hits ity and nothing would be able to move on it.
 
Famine
Imagine four horses. Each has the same strength as the others. They are attached to your four limbs and progress away from you in "opposite" directions (90 degrees apart from each other).

Each horse's force in one direction is cancelled out by the force of the horse going in the other direction. There is no net force. You'll still be torn limb from limb though.
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Thread necro thanks to a link from another thread, just because Famine trolling with Physics is just too good to pass up.
 
My contribution to the ressurection of the thread:

If you got yourself to the Earth's center of gravity, you would be suspended there weightless. You would not be torn apart by gravity in all directions, any more than you get crushed on the surface. (And Famine never said you would be!)

But unless you had a really very sturdy shell, you would be crushed by the air pressure. See, at the surface, under a 100 mile or so column of air, you are exposed to 15-some-odd pounds of pressure on every square inch of every surface of your body. Wonder what that amounts to under a column around 4 thousand miles high? (Even though some of it in your immediate vicinity is actually weightless, as are you?)

The problem with that pressure calculation is that while you are at the center of gravity, that gravity is not acting all from that point. My ignorant self doesn not know how to figure the air pressure that builds in your little tunnel to the center. I just know it would be rather significant.
 
I don't think you'd suspend their perfectly weightless and in mid-middleoftheearth-air, as you'd still be susceptible to tidal forces from the moon, sun and everything else in the universe.

At least that's what happened when I was last at the centre of the earth.
 
I was torn all night with this question.

The mass of the earth that influences you standing on the surface, would it be different then the mass of the earth that influences you finding yourself in the middle.

My first reaction, not that much, it is the same earth, so coming to the conclusion:

WFooshe You would not be torn apart by gravity in all directions, any more than you get crushed on the surface.
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But distance plays a role in these forces.
Wikipedia Newton's law of universal gravitation states that every massive particle in the universe attracts every other massive particle with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
Click to expand...

Some numbers from Wikipedia:
We are on top of the crust:
Density
2.2&#8211;2.9 g/cm3
Click to expand...

In the center of the earth we will be at:
Density
12.8&#8211;13.1 g/cm3
Click to expand...

So we are a lot closer to a lot heavier part of the earth, giving a lot more forces on you.
Actually the closer fitting of the protecting "pod" would be the greater the force.

edit: Forgot the original question: Estimate at this time, you would have trouble to escape from the forces in the middle of the earth if you succeed to survive them.

Edit2: forgot the tunnel, a tunnel in the "low viscosity liquid outer core" can not exist, so it all remains very theoretical. I have 1 hope for you:
Moses stretched out his hand over the sea, and all that night the Lord drove the sea back with a strong east wind and turned it into dry land. The waters were divided.
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Divine intervention, but then what do physics still matter?
 
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