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Has the age old question ever been answered ?


Graham
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When I was chopping up fire wood today I got to thinking.


I know my thoughts would have been better focused at missing my fingures with the axe but you know how it is.


My thought process went something like this.


 


Not wanting the off cut of the wood to fly up and clout you.


 


You swing the axe and it bounces off the wood.


So you put a bit more force behind the next swing and so on untill the wood breaks.


 


This got me thinking about the age old question of what happens when an irrestable force comes into contact with an imoveable object .


 


Has this question ever been answered ????


 


Would a stale-mate ensue ????


 


Would the irrestable force keep building ????


 


If it did keep building would there ever be a point where it would win the battle and if it did what would be the result ????


 


Sorry just a bunch of random thoughts but I would love to hear anyones ideas on the final outcome.

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Erm..........


 


Think of it this way, force = mass x velocity yes? Therefore the "force" hitting the immovable object must have some mass and some velocity. The immovable object has no velocity but a mass, in theory the force is zero as velocity is zero, anything multiplied by zero is therefore zero. However, the force exerted upon it will be translated into an equal and opposite force, so although the immovable mass would remain stationary, it would act with an equal and opposite force upon the force applied, this in theory would repel the force. It's easy to see in action with a Newton's Cradle.


 


I would say that the two objects here would need to be of infinite density to react in the same way as described, otherwise the energy would just get absorbed by the immovable object, or if the immovable object was substantially denser than the force being applied the force would pass around it, some would bounce back off but would be picked up by the other bits and would get swept past. In other words, unless both were of the same infinite density force would be dispersed around and off the immovable object much the same as water passes around a rock in a stream.


 


Edit to add:


 


Just thinking back to the immovable object having zero energy I am wrong. It's actual velocity is never zero it would have half of the relative velocity between the two objects.


Edited by Perkil8r
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Mike that theroy is ok if a bit too literal for my thoughts.


But taking your analergy of the rock in a stream.


What it the rock was a dam and there was no where for the force to go.


As it is an irresistable force its mass must keep growing to make it an " irresistable " force.


Like wise the Imovable object must also have infinite mass to resist the force.


Some where there must be a point where whatever is supporting the imovable object gives way.


Then what ????


 


Then again A "force" need not have any mass at all.


Magnatism, gravity ect.


 


In fact Magnatism has neither mass or velocity but it is still one of the most powerful forces known to man.


Edited by Graham
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As I see it, a Universe that has an irresistible force cannot contain an immovable object by definition, because if the force is irresistible then that force can move all objects in the Universe. Vice versa if there is an immovable object then that can be no such thing as an irresistible force. So they can never meet and the question is invalid. Cop out maybe, but it makes the maths a lot easier, and I'm all for that!


Angus


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Thats how I see it as well Angus the irresistible force and the immovable object can't both exist in the same universe, because each negates the possibility of the other. If an irresistible force exists, then there can not be an immoveable object, because then it wouldn't be an irresistible force. 

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Purely in the intrest of expanding this you will have to forgive me for playing devils advocate here but.....


 


Surely that would be the same as saying matter and anti matter cannot exist in the same universe ????


Please correct me if I am wrong but doesn't modern thinking say that both exist in the universe.


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Purely in the intrest of expanding this you will have to forgive me for playing devils advocate here but.....

 

Surely that would be the same as saying matter and anti matter cannot exist in the same universe ????

Please correct me if I am wrong but doesn't modern thinking say that both exist in the universe.

 

Simple answer is no, it is not the same. The name perhaps should be changed to wierdmatter instead of antimatter, or awesomestuff :lol: Think of antimatter in the same way as electric charge, you have positive and negatively charged particles, they can exist and indeed do.

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Fair enough Mike that clears that one up.


Awesomestuff --- Now that has a certain ring to it,,, I like that. :lol:


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Amazing what chopping wood does for you  :lol:


 


I never think like that....


 


But then again I never chop wood.


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Amazing what chopping wood does for you  :lol:

 

I never think like that....

 

But then again I never chop wood.

 

 

Maybe you should start :lol: :lol: :lol:

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Does gravity not become an irresistible force once it becomes strong enough (black hole) and also one of these would be fairly immoveable. I postulate that the irresistible force and immoveable object are one and the same thing.

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Does gravity not become an irresistible force once it becomes strong enough (black hole) and also one of these would be fairly immoveable. I postulate that the irresistible force and immoveable object are one and the same thing.

But black holes don't hold on to everything they only eat things that pass the event horizon, therefore they have a finite mass.....

 

Interesting idea there Tobias.

Do you still have 10 fingers?????  :P

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I've just figured something which defies logic in some ways but follows it 100%


 


A black hole has a mass but with infinite density and therefore infinite gravity. If you multiply infinity by 2 it is still infinity, therefore I conclude that the same sort of thing would happen (if it were possible to have such a thing as an immovable object and an infinite force) and they would combine into one mass of infinite energy and mass. And that my friends is how the internet works :lol:


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A black hole is a point of singularity, in laymans terms it has a physical size of less than a very small thing. Gravity is determined by the mass and the size of the object or in effect it's density. Because it has effectively no size it has infinite density meaning infinite gravity.


 


I realise that doesn't make it any easier to comprehend, but that's very roughly how it works as far as we understand so far.


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So what does infinite gravity mean? Does that relate to "strength" of the gravity or the distance that the gravity has an effect from the singularity, or both?

I'd have thought something with infinite gravity would be pulling me in right now....

I should read more astrophysics books.

James

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We are effected by the gravity of everything in the universe. Just most of it is really far away so it barely effects us. As to why we're not all smushed together into a massive smushy thing is down to inflation (or at least thats our best working hypothesis) I think :D

Edited by T A WOW
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So what does infinite gravity mean? Does that relate to "strength" of the gravity or the distance that the gravity has an effect from the singularity, or both?

I'd have thought something with infinite gravity would be pulling me in right now....

I should read more astrophysics books.

James

 

James, if you have around an hour to spare, have a listen to this lecture: http://www.astronomy.ohio-state.edu/~pogge/Ast162/Audio/Lect20.mp3 about black holes. The notes can be found here: http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit3/ just click the link to black holes. It is quite interesting stuff and fairly easy to follow if you have the notes up whilst listening. :) If you want to learn more, take a look in the Early Learning thread pinned to the top of the Astronomical Science forum, I have listed various resources for learning a fair bit online. I've stopped for a bit as I was getting over wowed with the information I was learning, it takes a while to comprehend some of the amazing stuff that's going on in our universe. It has though made me appreciate what I am looking at and imaging far more now I can understand some of the mechanics that drives it all.

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