Jump to content
Science Forums

Recommended Posts

Posted

OK, I think the that if an immovable mass encountered an unstoppable mass, the only outcome would have to be the annhilation of both. This is similar to the paradox of the infinite immovable mass and infinite force. What happens when they encounter each other?

Posted

Question: Shouldn't everything follow the laws of Physics?

Ok, ok you are probably thinking "another wise a$$", but i'm really not and all im trying to do, is to make things logical.

Ok, Sir Isaac Newton's law of inertia says that an object will stay at rest unless a outside force acts on it and similarly an object will move at a constant speed unless an outside force acts on it, it something along these lines... He (Newton) also came up with a law of ineraction that stated that for every action there is an equal and opposite reaction, meaning that if there is a force acting on an object the object should change in some way. Ok there is another thing to consider, momentum which is MVs-MVi or where M=mass and V=velocity. From physics we also know that the higher the momentum the higher the destructive power.

So finally to definitions; if by immovable object you mean a very massive object at rest (such as a big planet a star or a black hole) and by unstopable object you mean a very massive object at motion, probably fast motion (such as possibly a huge planet, meteorite, star or a black hole in motion maybe). It seems to me that in any case we will have a momentum that might equal to the speeed of the unstopable object at impact (here we would have a fairly big number, since the unstopable object was moving at a certain speed, and a very massive object(s) has a very powerful force of gravity so the acceleration of the objects toward each other would have to be calculated in and so forth).

Lastly from physics or at least from the part of it that i paid attention to in class (oh stupid, stupid me), i know that at a collision and explosion the summ of the mass times velocities initially should equal to the summ of the mass times velocities final (i.e. Sigma mv subscript i = Sigma mv subscript f)

I therefore suggest that three things can happen:

1) the masses will collide and form one that will be moving at 1/2 of speed of the unstopable object

2) the masses will collide and explode (like pool balls) so that unstopable object will stop and unmovable ovject will accelerate away at the speed of the unstopable object initially

3) the masses will collide but will heat up so much and create such conditions that the molecules they consist of will become unstable and detonate a chain reaction will follow and we will get yet another "BIG BANG"

Note: first two cases, you have to realize that some speed will be lost due to friction and heat energy that if factored in, will make the equasion above work...

Again I'm not trying to be a smart a$$ but i am trying to approach the question from a logical and scientiffic side.

I also appologize for the language used, hope it didn't offend anyone.

Posted

You completely miss the point. UNstoppable and immovable. Not just "alot" of momentum or "really" massive, we're talking hypothetical extremes. Something that absolutely cannot be moved meets something that absolutely cannot be stopped. What happens then?

Posted

So thats how they make jelly...

 

Something that absolutely cannot be moved meets something that absolutely cannot be stopped. What happens then?

 

Well, after thinking about it, the one that cannot move could rotate, causing the one that cannot stop to roll around it, however, this would slow down the one that cannot move...

Posted

Okay, I can appreciate the hypothetical situation here, but can someone provide me with a SINGLE example of an "unmovable" object? I can't think of one...

Posted

I was thinking about it yesterday and this thing popped up in my head and i can't seem to get it out.

Ok, what if the unstopable object is an energy or a wave with really high frequency(higher than any other wave we have ever recorded) and really high speed (of say 89,875,517,873,681,764 m/s) that has a property of not stoping or slowing down when going through masses? In that case if an immovable object meets and unstopable one absolutely nothing will happen, the unstoppable object will go though the immovable one and move on.

Posted

Eh...wouldn't that speed be superluminal by far?

 

Anyway, I still would like an example of an unmovable object. I think that is an oxymoron.

 

Tormod

Posted

Originally posted by: Tormod

Anyway, I still would like an example of an unmovable object. I think that is an oxymoron.

 

That is why I answered "Jelly".

 

With the admonition of sticking to the extremes of UNstoppable and immovable, there was nothing logical that coud be posted.

 

If something was so massive, it could not be STOPPED, there would not be enough energy to START it either. That would make it an UNMOVABLE object. Thus they are one and the same.

Posted

Well i think alexander did say some sensible things

indeed an immovable object (or better: an object only movable if the force wanting to move it is infinite) is an object with infinite mass (just by newtons F=m*a).

An instopable object can be defined in 2 ways:

1) the speed of the object is infinite (so any finite change in the speed will be neglegible). But this violates the fact that the maximum speed is the speed of light (which is finite)

2) The object has infinite mass (by the above argument)

 

So lets just asume our 2 objects have the same infinite mass M. What would happen then if we bounce them together? This problem now is exactly the same as any classical problem with the collision between 2 bodys of equal mass.

 

Well again (ignoring things like explosions; saying 'it all explodes' is no fun if our objects are infinite heavy it would be stupid if they fall apart if you kick them to hard...(but explosions (no annihilation which was also said; for that you need antimatter of some sort) are of course a valid sollution to the problem), also heat loss, deformations etc. are ignored) we have 2 possibilities (and everything in between these 2 extrema):

1) complete Elastic scattering. The moving body transfers all its momentum (without loss) to the body at rest. Energy conservation and the fact that the 2 bodys have the same mass then gives that the moving body will get at rest and the body at rest moves with the same speed as the original moving body did.

2) Complete inelastic scattering. The momentum is equally devided amongst the 2 body's. Sincs theus masses are equal, the will both move in the same direction with a speed half the original speed.

 

ps sorry tormod, this is still pure hypothetical, no infinite mass objects exist...

pps Note that the energy transfer is basicly infinite. The only way to avoid explosions is to also have the internal bonds that hold the object together are also infinite (they are not...)

 

Bo

Posted

Originally posted by: Tormod

I think the only theoretically immovable object that I can imagine would be the entire universe.

 

HEY! You beat me to it! I was just going to post something along that line! But as a question.

 

Is the Universe an INFINITE mass?

 

In fact could there have been an expansion after the BB if it needed an infinite amount of energy in order to cause an expansion of an infinite mass?

 

And if it was, would any contact with another object (another universe?) be along an expanding surface that at points of contact did not apply the infinite force of the total mass?

Posted

Originally posted by: Bo

1) the speed of the object is infinite (so any finite change in the speed will be neglegible). But this violates the fact that the maximum speed is the speed of light (which is finite)

As I understand it, it is NOT that the speed of light is the maximum speed. It is just that an object can not be accelerated PAST (or even up to?) the speed of light. But that it is theoretically possible for a particle to have a speed greater than light (tachyons?), but can not be slowed TO the speed of light.

 

IOW the speed of light is a line that can not be crossed, but just divides the two sides of it.

2) Complete inelastic scattering. The momentum is equally devided amongst the 2 body's. Sincs theus masses are equal, the will both move in the same direction with a speed half the original speed.

If we assume the infinite speed originally suggested, how can you have half of it?

Guest
This topic is now closed to further replies.
×
×
  • Create New...