Question about gravity.

Reply to post by alfa1

This is the correct answer.

You wouldn't stop in the middle, the speed that you travel at during the initial fall towards the centre would disallow you from stopping at the centre, you would carry on past the centre, reach the other end, and your velocity would reach zero, and you'd continue doing the same thing over and over.

Then again, in real life it would kill you, so theoretically that's what would happen if it didn't have deadly consequences.


Posted Via ATS Mobile: m.abovetopsecret.com

reply to post by SplitInfinity


Time (and spatial) dilation can be calculated with an equation called the Lorentz-Fitzgerald transformation.

The thing is that things need to be traveling at close to the speed of light before there is any appreciable spatial or time distortion away from 'flat' space-time.

Assuming a diameter of 12,715.43 km pole to pole (this is less than the diameter across the equator due to the distortion to the sphere by centrifugal forces), it gives us a radius (distance to the center) of 6,357,715 meters.

While at the surface, the acceleration due to gravity is 9.8 meters per second per second, this acceleration will diminish to zero at the center of mass. This does not mean that the velocity will decrease, in fact the velocity will be the greatest when the 10kg mass reaches the center of the Earth where the velocity would be about 12,350 meters per second.

Although my calculations are based upon approximate values, this is nowhere near the speed of light so I think relativistic (Minkowski space dilation) considerations can be ignored.

reply to post by moebius

You believe I know nothing about Physics eh? Let me ask you a question...there is a minimum and a maximum numerical number that Quarks must never exceed or be in a lessor number within a Proton or Neutron. What are those numbers both the Minimum and Maximum...and where do you believe the Quarks are going as they blink in and out of existence within a Proton or Neutron as they can numerically exist at quantities at both minimum or maximum as well as in between?

Also...provide an answer of what happens to the Gluons when Quarks blink in and out of existence as well as what happens to the Hadrons that are bound to Quarks by those Gluons.

And if you can...tell me what type of Vector Boson a Gluon is?

Split Infinity

reply to post by chr0naut

You are guessing as Special Effects that are most likely present in a Celestial Bodies Gravity Well have Relativistic and Physics Busting changing of Potential Kinetic Energy of a falling Object.

Split Infinity

reply to post by SplitInfinity


You're comparing the center of a black hole to the earth, claiming both are a singularity. Disregarding the question of whether earth could have a singularity, there's still one basic problem with what your saying. The strange effects of a black hole occur at the edge of the mass, not the center. So if your right, these strange effects would happen to say, a weight on a spring as it approaches the surface of the earth.

The only way your idea could be correct, assuming we're still comparing it to a black hole, would be if the center of the earth had an extremely dense core of super condensed iron or something. However, in order for the conditions given in the problem to occur, such a dense core would have to be removed in the first place.

This does beg an interesting question in my mind. Suppose a hole were drilled through the center of a black hole, and vacuum conditions were extant in that tunnel. Then a mass was released on the edge of that vacuum, according to Newtonian laws of mechanics, it would have to travel until it was the same distance from the mass, on the opposite side. Yet, relativistic physics informs us that once something crosses the event horizon, it can never exit.

Thus, newton's laws of motion are not always applicable.

Guess we'll never know until we drill that tunnel.

reply to post by moebius


Interestingly, Michael Faraday, one of the most important physicists ever, had almost no knowledge of, or ability in math. Being considered one of the best experimental physicist of all time. He discovered the faraday cage, the transformer, the electric generator. He discovered that a charge in motion gives rise to a magnetic field at 90 degrees to that motion. He was the first to postulate an electric or magnetic field, and the first to describe all of the lines of force around a magnet.

Couldn't do math, not even simple trigonometry.

Btw this is coming from a man who has passed math courses in calculus, discrete mathematics, and differential equations.

reply to post by renegadeloser

Well...I certainly would not want to be the one making a Tunnel through a Black Hole! LOL! I am not saying that an actual Singularity is present at the Center of the Earths Gravity Well...what I am saying is that an EXPRESSION of SINGULARITY is being Created and even though the Earth has no where near the Gravitational Effect of a Black Hole...it still has this Expression Present which allows for Special effect.
Split Infinity

Originally posted by SplitInfinity
reply to post by moebius

 

You believe I know nothing about Physics eh? Let me ask you a question...there is a minimum and a maximum numerical number that Quarks must never exceed or be in a lessor number within a Proton or Neutron. What are those numbers both the Minimum and Maximum...and where do you believe the Quarks are going as they blink in and out of existence within a Proton or Neutron as they can numerically exist at quantities at both minimum or maximum as well as in between?

Also...provide an answer of what happens to the Gluons when Quarks blink in and out of existence as well as what happens to the Hadrons that are bound to Quarks by those Gluons.

And if you can...tell me what type of Vector Boson a Gluon is?

Split Infinity

Simple question...what bearing of your post have on the topic of this thread?

You are talking particle physics and I see no bearing of that to the aforementioned topic of the thread. In fact, I see the original question, as you described it in a previous post, to be nothing more than an exercise.

I see individuals discussing light speed etc of the ball in free fall. Now with the absence of drag since there is no atmosphere, acceleration is not limited, or is it? However, at what point does the mass of the ball equal the mass that is creating the gravity well (which raises the question as to what the mass of the ball is)? As the ball approaches the center of the "tube" - is the tube contributing to the mass creating the gravity? If the ball is of ferrous material will the magnetic lines of force have an influence upon the ball?

But in my mind, the question is why does high mass create gravity which leads to the question will different mass balls accelerate differently.

This entire exercise reminds me of the three cowboys and $30.

Mikado

reply to post by SplitInfinity

I will pin point exactly where you are confusing the issue...in your Reply you used the word...PUSHES...as well as the word...TOWARDS. I will explain each words use as you see it and what the Reality of what is occurring truly is in your question.

To be clear on this I do not see it that way. I specifically said

I don't get why you view the center as a point to which all of Earth's Gravity pushes towards?

Why YOU view...... not me. I say that because that is how you're treating the center in this problem. You seem to think Gravity is concentrated at the center of Earth's mass when in actuality it's at equilibrium, "pulling" on the object in all directions outwards. Not "pushing" inwards to center having a "braking" effect.

The whole expression of singularity and comparing the center of Earth to a black hole doesn't seem logical at all, rather quite a leap in logic in my uneducated opinion.

In what way does gravity exhibit its force on a mass in a vacuum?

first,,, what does a vacuum have in it?

if a vacuum has forces of gravity acting within it,,, is it a vacuum?

I went and reread the first page of this thread.

I see some confusion between mass and weight. One is scalar and one is vectorial.

There is confusion over drag, thus the vacuum to eliminate it. If anyone here has college physics under their belt then they would know that "freefall experiments" are conducted in a vacuum. Therefore, the initial hypothesis from the original poster had the object in a vacuum since it is essentially a freefall experiment.

This argument has been going on, in some manner, since Aristoteles.

Mikado

Originally posted by renegadeloser
reply to post by moebius

 

Interestingly, Michael Faraday, one of the most important physicists ever, had almost no knowledge of, or ability in math. Being considered one of the best experimental physicist of all time. He discovered the faraday cage, the transformer, the electric generator. He discovered that a charge in motion gives rise to a magnetic field at 90 degrees to that motion. He was the first to postulate an electric or magnetic field, and the first to describe all of the lines of force around a magnet.

Couldn't do math, not even simple trigonometry.

Btw this is coming from a man who has passed math courses in calculus, discrete mathematics, and differential equations.

edit on 28-10-2012 by renegadeloser because: (no reason given)

That is false. Although he didn't have a formal eduation in mathematics, that doesn't mean he had no knowledge of mathematics. They are two VERY different things. He did have mathematical ability and knowledge, just no "degree" in it.
He was very capable of doing mathematics, as is any scientist, especially one involved with physics and chemistry where it is used often.
You have taken the fact he didn't have a formal education in mathematics and extrapolated it into thinking he couldn't do math. That is not the case. (or read an article that extrapolated it, either way, it's still false)

Originally posted by Mikado
I went and reread the first page of this thread.

I see some confusion between mass and weight. One is scalar and one is vectorial.

There is confusion over drag, thus the vacuum to eliminate it. If anyone here has college physics under their belt then they would know that "freefall experiments" are conducted in a vacuum. Therefore, the initial hypothesis from the original poster had the object in a vacuum since it is essentially a freefall experiment.

This argument has been going on, in some manner, since Aristoteles.

Mikado

This is not a free fall experiment. The 10kg mass was not dropped it was just placed inside the vacuum tunnel.

The 10 kg mass doesn't have any mass underneath it self. Because the vacuum tunnel goes through the center of earth and out on the other end. Earth is isolated from the vacuum by the walls of the tunnel.

What some people in here don't understand is the difference between a closed system and a open system. This experiment can not be looked upon as if it was a open system.

If the mass should sink by it self. The vacuum inside the tunnel must gain weight towards the center. But it doesn't. It is vacuum all the way to the other end. How would the mass know which way to sink? When there is equal pressure in both ends? The mass would not know where it should sink.

Originally posted by spy66
The 10 kg mass doesn't have any mass underneath it self.

Apart from the earth....

If the mass should sink by it self.

Of course it would sink, as it is under the effect of gravity.

Just why do you think a vacuum stops gravity?

How would the mass know which way to sink?

by gravity....

When there is equal pressure in both ends?

??? you make no sense.

The mass would not know where it should sink.

it moves down due to gravity.

Originally posted by spy66


This is not a free fall experiment. The 10kg mass was not dropped it was just placed inside the vacuum tunnel.

The 10 kg mass doesn't have any mass underneath it self. Because the vacuum tunnel goes through the center of earth and out on the other end. Earth is isolated from the vacuum by the walls of the tunnel.

What some people in here don't understand is the difference between a closed system and a open system. This experiment can not be looked upon as if it was a open system.

If the mass should sink by it self. The vacuum inside the tunnel must gain weight towards the center. But it doesn't. It is vacuum all the way to the other end. How would the mass know which way to sink? When there is equal pressure in both ends? The mass would not know where it should sink.

edit on 27.06.08 by spy66 because: (no reason given)

ummmm, exactly what is it that you THINK free fall is?

Originally posted by SplitInfinity
reply to post by chr0naut

 

You are guessing as Special Effects that are most likely present in a Celestial Bodies Gravity Well have Relativistic and Physics Busting changing of Potential Kinetic Energy of a falling Object.

Split Infinity

Then please identify clearly what these relativistic "Special Effects" are in terms of magnitude, direction of action, units and any other consequential parameters. It is vital to the topic thread that they be made clear and unambiguous. All I'm seeing is scientific sounding words that are so vague that they can be applied any number of ways.

The only relativistic effect that I know that is relevant to the thread topic is the distortion of space-time by gravitation. This is a fairly simple positional distortion to location, away from the nominal 'flat" grid of space-time and it is tiny, even for something the size of the Earth.

You also need to realize that, without actually calculating the sizes (magnitudes) of things, that you are dealing ENTIRELY with metaphorical conceptions. While these metaphors make conceptualization easier, they are only LIKE the thing they describe. They are NOT the thing that they describe, and so may be misleading.

This is why it is vital to have a mathematical way of determining values. When you begin to "play" with the numbers, you actually begin to get a feel of the sizes of things and size IS important in the world of physics.

I await your response.

Originally posted by spy66

This is not a free fall experiment. The 10kg mass was not dropped it was just placed inside the vacuum tunnel.

The 10 kg mass doesn't have any mass underneath it self. Because the vacuum tunnel goes through the center of earth and out on the other end. Earth is isolated from the vacuum by the walls of the tunnel.

What some people in here don't understand is the difference between a closed system and a open system. This experiment can not be looked upon as if it was a open system.

If the mass should sink by it self. The vacuum inside the tunnel must gain weight towards the center. But it doesn't. It is vacuum all the way to the other end. How would the mass know which way to sink? When there is equal pressure in both ends? The mass would not know where it should sink.

When you have hold of something and release it, and it falls due to gravity, this is the very definition of dropping the object. An object in a vacuum that is affected by gravity, and that is released, falls. It was, therefore, dropped.

The mass doesn't "sink" due to gravity, the more normal way of describing the movement is to say it falls due to gravity. Sinking implies buoyancy. In a vacuum there is nothing to buoy up anything.

Similarly, a vacuum is an absence of matter. Matter has mass and a vacuum has none. A vacuum, therefore has no weight (weight = mass x acceleration due to gravity) at all, it does not get heavier in the center like a column of air. Also, since it has no weight, there is nothing to give a vacuum any pressure. It has no pressure at either end, or in the middle. A vacuum = no pressure.

The 10kg mass does not need to "know" anything to fall. It follows the shortest path through space-time with all energy conserved.

reply to post by hellobruce


What gravity effects the 10kg mass?

There is no gravity inside the tunnel. Earths gravity is isolated by the tunnel. It does not effect the 10kg mass.

reply to post by spy66

Earth's gravity affects everything which is close enough to it. Including the Moon.

reply to post by spy66

There is no gravity inside the tunnel. Earths gravity is isolated by the tunnel. It does not effect the 10kg mass.

Is that a special condition of the experiment or do you just believe for some reason that a vacuum would eliminate the efffect of Gravity on the object?