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ArcticMyst Security by Avery

Large Hadron Collider.

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I think you would die before getting compressed to the maximum.And other people wouldn't see anything because all of the blackness. :p Maybe you would just die before from the huge gravitational acceleration right after you lose conciousness.

Ok so what happened? I didn't read anything, did it get delayed again? Untill when? :-?
 





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Switch said:
I think you would die before getting compressed to the maximum.And other people wouldn't see anything because all of the blackness. :p Maybe you would just die before from the huge gravitational acceleration right after you lose conciousness.

Ok so what happened? I didn't read anything, did it get delayed again? Untill when? :-?

Yes, it got delayed till may. ;)

Also, I do have a hard time believing that you could get killed by gravity while your free falling. :-/
In a car you sit stationary and the car uses brute force to make it move, so you feel a couple G's when its accelerating. Now lets try getting in the car and dropping through the sky. would you feel anything because both you and the car are accelerating at a constant rate. Theres pretty much no air in space (lets just assume that for this experiment there it NOTHING between you and the black hole).

If you were in a ship and you are "falling" down into a black hole would you feel anything? I'm not sure but the farther down you go the more front of the ship is getting pulled on more then the back so you are stretched into a tiny strand of particles that go "into" the black hole and....Then what happens? :-?

Is it possible for you to feel anything when your in free fall and theres no "air" to slow you down?

--hydro15
 

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Well the Earth has a ~9.81 m/s[sup]2[/sup] gravitational acceleration so skydivers are ok as far as G forces go.But even the toughest people in top of the line suits loose conciousness at around 12-14G as far as I know.Now a black hole has a field sh!ittons stronger than that of the Earth and will subject you to alot more than 14G by my estimates....a lot more, right? :-/

you are stretched into a tiny strand of particles

Yea, human streched into a tiny strand of particles spells dead human to me. :p

Is it possible for you to feel anything when your in free fall and theres no "air" to slow you down?

Yea, intertia. :p Air has nothing to do with it.
 
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Switch said:
Is it possible for you to feel anything when your in free fall and theres no "air" to slow you down?

Yea, intertia. :p Air has nothing to do with it.

This leads to a good physics question that a LOT of people miss, at least in my experience. Maybe we gots us some smart people here that won't miss it. And, I think it will answer the question about falling toward the black hole as well.

Why do astronauts on the space shuttle, the space station, etc, feel weightless while out there?
 

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Um, because they're too far away from the Earth? :-/

Taking Newton's law of universal gravitation into account: F=G(m[sub]1[/sub]m[sub]2[/sub]/r[sup]2[/sup]) where r is the distance between the two bodies(earth and astronaut here) so in our case r is too big so F is too small.They are almost weightless because F is almost 0? Or it has something to do with revolving around the Earth and centrifugal force entering the equation? :-/
 
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Switch said:
Um, because they're too far away from the Earth? :-/

Taking Newton's law of universal gravitation into account: F=G(m[sub]1[/sub]m[sub]2[/sub]/r[sup]2[/sup]) where r is the distance between the two bodies(earth and astronaut here) so in our case r is too big so F is too small.They are almost weightless because F is almost 0? Or it has something to do with revolving around the Earth and centrifugal force entering the equation? :-/

:-X.  Keep thinking, Newton's law there is a good step in the right direction, and your other thoughts as well.

Note, purely aside, "centrifugal force" doesn't really exist, it's a convenience force invented to make some calculations easier sometimes and because it "feels" right when you experience it.  The real force is the centripetal force.  When you feel "centrifugal" force, you're really feeling the action of a centripetal force.  That bit of knowledge can be a good one to impress physics teachers earlier in your education, since that's another common misconception.


---Crap, I've hijacked a thread.   :-[ If anyone is offended, I'll remove posts and move along, but it kinda seems the discussion has gone off-course anyway?  :-/
 

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Hijack my thread all you want, as long as the hijacking is interesting, just there I learned something new ! ;)

-Adam
 

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Well, CERN deserves their thread hijacked, they delayed the LHC way too much :(

Ok I think I've got it.I think it's explained by the orbiting phenomenon.Earth's gravity acts as a centripetal force (the one that pulls them to the center of the Earth and to the center of the curvature of the motion,right?) So you have this force constantly changing the direction of their velocity so they're basicly falling around the Earth, which is what orbiting really is.So since they're falling, they're being accelerated, so now inertia comes in.Inertia is the tendancy of an object to maintain a constant velocity, so while the shuttle is being accelerated by gravity, it experiences intertia , which cancels the gravitational pull and the shuttle with astronauts becomes weightless.

That sounds about right :-/ except I don't understand where the rotation comes from in the first place? Why don't they fall directly toward the center of the Earth?

So anyway, moving on.When in free fall or orbit, you basicly don't experience G forces? :-/
 

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I would guess that: Let's say you weigh 200lbs, then as you get "sucked" into a black hole from the over whelming gravitational pull, then you would all of a sudden weigh something like 20,000lbs all the while being compressed to the size of 1/100000 of an atom.   Sounds pleasurable.  

Edit: then you would wake up in virtual land.
 

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Ace82 said:
I would guess that: Let's say you weigh 200lbs, then as you get "sucked" into a black hole from the over whelming gravitational pull, then you would all of a sudden weigh something like 20,000lbs all the while being compressed to the size of 1/100000 of an atom.   Sounds pleasurable.  
I dunno if that is correct from a scientific point of view.Weight and mass are not the same thing, mass is a property of the object while weight is a force.1lbs is a unit of mass, so when you say something weighs 200lbs you are refering to its mass, and mass can't change regardless of the gravitational field the object experiences. :-/
 
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^^^Word, nice.  Yes, it's because the shuttle is in free fall, pure and simple.  It, and the people in it, are being accelerated by earth's gravity.  But, it's moving forward fast enough that by the time it falls some, the earth has already "curved away from" the shuttle  It's moving forward fast enough that it falls PAST the earth instead of into it, and you get orbit.  Since it's constant free-fall, you experience weightlessness.  If you work out the gravitational law, you get some like you only lose 11% of the force of gravity when you get to shuttle altitude, or something like that, but certainly not all of the force of gravity.  From a pure gravity point of view, if you weigh 100lbs on earth, you'll weigh 89lbs at the altitude of the shuttle if you had a way to measure the weight.

And you have the explanation of mass vs. weight almost right.  You're right, mass doesn't change, but weight does.  Weight is the effect of the force of gravity on a mass.  Your mass on earth and your mass if you were on the moon will be equal.  But you will weigh less on the moon than on earth since the force of gravity is smaller on the moon due to it's smaller mass.  The units get funky and it does get confusing because people use it both ways, but to me and most people I know, lbs are units of weight, and they are actually units of force.  A pound does not always correlate directly to kilogram, the SI unit of mass, a pound correlates to a newton, the SI unit of force.  So the unit pound is actually a force (at least the way every science person I know of does it), so it is a weight, not a mass.  This is another area where still using "standard" instead of metric in the US is stupid, because some people correlate kilograms to pounds, which is ok, but it makes things confusing when you use pounds as both a mass and a force.  But in general, I think most people think of them as a force instead of a mass.
 

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I had no idea, I was absolutely sure that pounds are units of mass.Even my cellphone unit converter converts from kilograms to pounds or viceversa.I do live in Europe and always use SI.I can handle inches , feet , yards and miles, but everything else I get lost in.So anyway, kg vs lbs is not just a numerical difference, it's a pretty dam big difference ,huh? :p

It's always nice to clear things like this up.I had a horrible physics teacher in highschool....basicly 4 years of wasted physics classes.And now I get lost in the basic college stuff too. :-/
 
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Yeah, it's one of those confusing things about the stupid standard system; it can be a weight or a mass, but the "more better" way to think of it is as a weight/force.  That way if you ever have to do any other calculations with standard system with using pounds as force, or pressure in lbs/sq.in, or ft-lbs of torque, you'll be better equipped and not going "wait, I thought that was mass...". And of course, as long as you're in constant gravity, you can do a direct conversion of weight/force due to gravity straight to mass and back again. Since earth is pretty much a constant gravity, even if you consider it only a force, the conversion still works as if it were a mass.

I'm in a science field, and by and large people use SI exclusively (although I did once have to do a thermo problem in temperature units of Rankin, I was pissed and it was a completely needless pain in the neck to make us do it in Rankin just to prove it worked when SI is SO much simpler and easier).  I can only hope that further improvement in science education here in the US will push SI more into mainstream and popular usage in the US, as maybe that science subset of US population will grow and push it on everyone else.  ::prays::
 
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Switch said:
Well the Earth has a ~9.81 m/s[sup]2[/sup] gravitational acceleration so skydivers are ok as far as G forces go.But even the toughest people in top of the line suits loose conciousness at around 12-14G as far as I know.Now a black hole has a field sh!ittons stronger than that of the Earth and will subject you to alot more than 14G by my estimates....a lot more, right? :-/

you are stretched into a tiny strand of particles

Yea, human streched into a tiny strand of particles spells dead human to me. :p

Is it possible for you to feel anything when your in free fall and theres no "air" to slow you down?

Yea, intertia. :p Air has nothing to do with it.

Maybe it will look like that to somebody who is watching the person fall into the black hole.
As we know falling is easy but the landing is the hard part.

To explain this better lets just say your in a vacuum (and not dead lol) and you are in a constant free fall. Now consider this, you just accelerated without feeling an G's because gravity
pulls on every part of your body. Cars don't work like gravity (you do get some G's when you accelerate) because theres nothing to cancel out your inertia. When your stationary you feel gravity trying to pull you down but in a free fall you don't feel gravity because your not trying to resist it.

If you tried to stand on a black hole (which I'm not sure is possible) you would get crushed because theres resistance.

Wow, this sounds confusing even to me. :eek: This is all just theory because the only way to know EXACTLY what happens when you "jump" into a black hole is to try it. :-/

--hydro15

LOL heres a funny pic-->
 

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FrothyChimp said:
[quote author=Hemlock Mike link=1220462301/0#19 date=1220486890]I don't think LHC can produce a singulary. It is looking for Z0 and other particles with far less than the energy needed to make a tiny black hole.
---- do I here a sucking sound ? ;D What is the smallest mass needed to make a sustaining black hole?

Mike

Sustained black holes are roughly 1.5-3.0 and larger solar masses. However, it is entirely likely the LHC will generate mini-black holes. The energies available in the TeV (trillion electron volts) will slam protons together at such energies as to compress their masses into a very, very small space. If they indeed create black holes at the LHC it will lend support to string theory with its multiple dimensions. The critical component to black holes is very large mass to generate the gravity to create a singularity. In our normal macro world gravity is pretty predictable. If you half the distance between masses you increase the gravity by a factor of 4. Now bring those distances very close (a limit approaching zero) and the gravitation approaches infinity (well sort of). The masses of the particles are very small and bringing them close does indeed increase the gravitational field but not quite enough for them to collapse into a singularity based on classical physics. If, however, the multidimensional world of string theory is correct, the gravitational effects of these dimensions will provide additional force to cause a proton-proton collision to create a singularity. Basically, if the distance between the particles increases more than a factor of 4 each time the distance is halved then the gravitational field must be assisted from somewhere outside our three physical dimensions.

Now these mini black holes will not engulf the earth and the solar system as the unenlightened fear mongers claim. Quantum physics predicts that the smaller the black hole the more energetic the release of Hawking radiation. Thus the mini-black hole comprised of only a portion of each proton (the rest is blown apart in a mass of collision fragment particles) will evaporate instantly. Furthermore, the physics predicts a specific set of decay particles to be generated as it evaporates. These particles are detected all the time coming from the upper atmosphere as very high energy cosmic rays bombard the nitrogen and oxygen atoms in the atmosphere. So there are min-black holes being created and evaporating all the time 60-70Km above us. These cosmic rays collisions are in the hundreds of trillion electron volt range. Hopefully, the LHC can achieve black hole formation.

Here's a though that will twist your noodle. Once we get to playing around with multidimensional space, it is theoretically possible to create a big bang and a brand new universe that will expand as large as our universe. Of course it will not destroy our universe as, like our universe, it will create its own space as it grows.

By the way, the girl doing the LHC rap video is a recent physics graduate of Michigan State University, my alma mater. She cut her teeth on our fully functioning super conducting cyclotron. Ok, so a cyclotron is old school but having been there myself, it's pretty freakin' impressive.[/quote]

I didn't know that black holes needed to have a specific amount of mass in order to produce a singularity. I always thought it was density that counts and not mass. :-? Was I wrong?

--hydro15
 

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A singularity can be seen as a "point" with 0 volume and infinite density, infinite gravitational forces , right? So if gravity were infinite everything everywhere would just get sucked in by it.So if a singularity actually exists outside theory, something must be stopping it to suck the whole universe in , right? So maybe if a singularity would be formed on Earth it wouldn't cause everything around it to collapse and we could get on with our normal lives because it would be sorounded by the same kind of "event horizon" thingy....maybe... ? :-/
 




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