# When an irresistable force meets an immovable object

Supposedly, it's impossible for both to exist. If they met, wouldn't the unstoppable force just ricochet of the the immovable object?

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Ricocheting requires being stopped for a split second and changing course, so that wouldn't count as unstoppable.  Yeah, I'm gonna go with that.

Most likely, the forces generated would punch a hole in the fabric of reality and you'd get your answer just as you blinked out of existance. Or it would become the fabled fountain of kittens.

Either way I win.

No, because then it would have been stopped.

They collide and the fabled fountain of kittens bursts forth from the ground, spewing awesomeness and cute in every direction, and before long you will begin to hear a yipping sound as the puppies make their way out of the fountain as well!

What I think would happen is that the force would meet the object, and since this force is unstoppable, not unslowdownable or unchangedirectionable, it would find it's way around the object by exerting force in many directions and following the path of least resistance.

Well, obviously the Master turned the TARDIS into a paradox machine so that he could summon the Fabled Fountain of Kittens. (Sorry, just got into DW. Kinda in love).
Then god would just destroy them both

Well, logically speaking (or as logical as this BS hypothetical situation can get) the only way a force could be irresistible is if it's being propelled by an infinite amount of energy.  The only way an object could be immovable is if it has an infinite amount of mass.  Something moving at the speed of light crashing into something with infinite mass would create and explosion that would make the Big Bang look like a fire cracker.

Of course, infinites don't actually exist.

Logically speaking, the irresistable force would just move everything around said object.

Space is a funny place.

Each one could supposedly exist in separate worlds, just not in the same. If there is an unmovable object than the irresistable force would not be able to move it, and if it could, then the object would not be unmovable
Newtonian mechanics state that an unstoppable force (where we assume that Fnet = infinity) must have either infinite mass or infinite velocity, and negligible friction. Of course, since an object with infinite mass becomes a black hole, the mass must be finite and the velocity infinite. And, also of course, special relativity states that objects that have mass cannot travel at velocities at or above the speed of light, so the force must be massless.

A similar principle can be applied to the immovable object, except that a stationary object has a net force of zero, meaning that, once again, it must have infinite mass or infinite velocity, and zero of the other. We can ignore friction because the object must be stationary, i.e. having zero velocity, because in order to classify as an "object" it must be comprised of matter, and all matter (however miniscule) has mass.

In order to determine the resultant mass/velocity of the collision, we have to use the conservation of momentum law, because momentum is conserved in all collisions. My calculation is linked to below. (I assumed that everybody knows the formula for momentum, but in case you don't, momentum = mass * velocity)

http://img4.imageshack.us/img4/6529/momentumofinfinitereact.png

As you can see, the next logical step would either be a division by infinity (which is undefined, so we can ignore it), or dividing by zero. And as everybody knows, dividing by zero creates a black hole that swallows the universe.
Actually the unstoppable force would just break throught he immovable object because nobody ever said how hard the object was.