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Sang-drax
02-10-2005, 05:47 AM
Let's say we have a ball and a hole. The ball is slightly larger than the hole, so it won't fit.

Now we throw the ball at an enormous speed direclty towards the hole. What happens?

(i) (From a person standing beside the hole's POV)
The ball is slightly smaller than the hole and will pass through.

(ii) (From a person standing on the ball's POV)
The hole is much smaller than the ball, so it'll crash when it arrives.


What will happen?

laserlight
02-10-2005, 06:23 AM
The ball's mass increases drastically leading to an increase in size so it covers the whole hole and more?

frrossk
02-10-2005, 06:25 AM
What will be the point of view of a person standing between ball and hole? :D

Govtcheez
02-10-2005, 06:59 AM
> The ball's mass increases drastically leading to an increase in size so it covers the whole hole and more?

Just because it increases in mass doesn't mean it gets larger.

laserlight
02-10-2005, 07:06 AM
Just because it increases in mass doesn't mean it gets larger.
That's why I assumed that it does.
On second thought, maybe there is negligible increase in mass, but instead the ball burns up and the little that's left of it passes through the hole.
hmmm....

Clyde
02-10-2005, 10:19 AM
What will happen?


I have no idea, but be sure to post the answer when you find out.

Sang-drax
02-10-2005, 10:36 AM
What will be the point of view of a person standing between ball and hole? :D

The position doesn't matter, only the relative speed to the ball.


The ball's mass increases drastically leading to an increase in size so it covers the whole hole and more? No.

Thantos
02-10-2005, 10:37 AM
Well you said that the ball is slightly larger then the hole. If its thrown with enough force and if its thrown accuractly then the force of the ball hitting the hole's edges would be enough to reshape the ball so that it would fit through the hole. Once it was through the hole the ball would return to its native shape.

CornedBee
02-10-2005, 10:38 AM
In any case, it has nothing to do with relativity. Oh, and the person between ball and hole will get the ball in the face.

Lithorien
02-10-2005, 11:19 AM
The ball will fit through the hole, because as it goes faster, it elongates and thins out.

Brian
02-10-2005, 12:09 PM
perspective != relativity

laserlight
02-10-2005, 12:53 PM
perspective != relativity
Sang-drax might be thinking of frames of reference, but I'm not exactly very strong in the concepts involved in relativity to comment with any authority on it anyway.

Sang-drax
02-10-2005, 01:25 PM
OK, I think I've figured something out.
If the ball travels perpendicularly towards the hole, the ball will only look shorter in the direction of motion to the observer. The ball will look like somebody sat on it.
Same for the hole.

Thus, both observers will agree on the size of the ball in the other dimensions and it still won't fit.

Sounds reasonable.



perspective != relativity

No, but things will look different from different points of view. Events can even be happening in different order, depending on your relative speed to the objects you study.

major_small
02-10-2005, 03:54 PM
who cares? stop trying to put the square peg in the round hole... the solution is simple: make the hole bigger or the ball smaller.

either way, if the ball is malleable enough, and the force is constant, the ball will elongate into an ellipse and fit through the hole, but as you said, the ball is 'thrown' at the hole, so now it comes down to time. if the ball has enough time to regain it's shape by the time it hits the wall, it will hit the wall. if the ball gets to the hole before it regains it's shape, it'll get through.

Zach L.
02-10-2005, 05:19 PM
Uhh... Been a bit since I've done relativity, but shouldn't the ball only "deform" in the direction it is traveling. (And no, it won't turn into an ellipse and thin out.)

So, if it's going straight for the hole ("straight" meaning directly at some projection of it -- i.e. at an angle would work so long as the trajectory takes it through the hole), then it should make it through so long as it would under non-relativistic circumstances. If it isn't on a trajectory that goes through the hole, it has bigger problems to worry about.

Sang-drax
02-10-2005, 06:01 PM
Uhh... Been a bit since I've done relativity, but shouldn't the ball only "deform" in the direction it is traveling. (And no, it won't turn into an ellipse and thin out.)
Yes, that was what I was trying to say in the post above.

The high speed of the ball doesn't change anything in this case.

major_small
02-10-2005, 10:40 PM
Uhh... Been a bit since I've done relativity, but shouldn't the ball only "deform" in the direction it is traveling. (And no, it won't turn into an ellipse and thin out.)

So, if it's going straight for the hole ("straight" meaning directly at some projection of it -- i.e. at an angle would work so long as the trajectory takes it through the hole), then it should make it through so long as it would under non-relativistic circumstances. If it isn't on a trajectory that goes through the hole, it has bigger problems to worry about.
we just basically said the same thing, except you used more correct wording and I was assuming the trajectory was exactly perpendicular to the plane the hole was in.

Zach L.
02-11-2005, 01:32 PM
Alright... I just misunderstood the wording (major_small, I still can't quite understand yours... oh well).

Cheers

xxxrugby
02-11-2005, 02:14 PM
If the speed is very very fast. And the ball is not very good fill with air. Then it will become like Rugby Ball. And you yan put it in your cheramic pen.
But if is still to big. Or very well filled with air. With the increased speed also force of hitting the hole is increased, and beacuse of that when ball hit the hole. It will go into holle.

Sang-drax
02-11-2005, 04:05 PM
If the speed is very very fast. And the ball is not very good fill with air. Then it will become like Rugby Ball. And you yan put it in your cheramic pen.
But if is still to big. Or very well filled with air. With the increased speed also force of hitting the hole is increased, and beacuse of that when ball hit the hole. It will go into holle.
Sorry, I don't understand. :(



either way, if the ball is malleable enough, and the force is constant, [...]
The deformation due to high speed has nothing to do with malleability.

I was only interested what would happen from a relativistic point of view, and I think the problem is solved. The ball will only deform in the direction of travel, and the speed will not affect its possibilities to travel though the hole.

Zach L.
02-11-2005, 05:05 PM
To "clarify" a bit:

The ball will really contract (not elongate) on the direction of travel. And, no force is necessary (and in fact it complicates the picture beyond the realm of special relativity). The "deformation has nothing to do with the mechanical properties of the ball, and from the ball's own perspective (or rather, the observer on the ball), there will be no deformation at all.

Lurker
02-11-2005, 09:42 PM
Let's say we have a ball and a hole. The ball is slightly larger than the hole, so it won't fit.

Now we throw the ball at an enormous speed direclty towards the hole. What happens?

(i) (From a person standing beside the hole's POV)
The ball is slightly smaller than the hole and will pass through.

(ii) (From a person standing on the ball's POV)
The hole is much smaller than the ball, so it'll crash when it arrives.


What will happen?

Subject A (thrower) throws Subject B (said ball). A decides to go for the fastball he's been practicing for (a few steroids, but he kinda apologized!) and goes for it. Subject B screams in terror, but it is too late. B has been thrown at a blistering speed of 20,000,001 mph! The whizz of his rubbery flesh skidding against the unforgiving air produces an acrid smell - B is on FIRE! Subject C (fireman) gets the extinguisher, but ALAS - B goes by to fast! A is standing, waiting, preparing for the amazing feat of Subject B meeting Subject D (said hole) in a clash of amazing physics! C is thrown back by the air force created by B. D prepares for impact: "MAN DECK! MAN DECK!". Subject E (other side of hole) screams shrilly in terror of the advancing ball. BOOOOOOOM! B hits D DIRECTLY on target. A pumps his fist up in the air in victory. B SHATTERS D and goes straight through Subject E. Because of the 22.324 dimension universe Subjects A, B, C, D, and E live in, B goes all the way around the world enough times to kill everyone. B finally burns up the last of his energy and EXPLODES, CREATING A GIGANTIMUS BLACK HOLE. This black hole eats EVERYTHING in the universe over a period of 12 hours, then collapses and creates a huge explosion. This explosion, after 15 billion years, is called the "Big Bang" by a large tribe on a planet in a Solar System on the edges of its galaxy.

EDIT: PHEWWWWWW.....deeeeeep breath.

EDIT2: Who gave me bad rep for this :mad: ?

gcn_zelda
02-11-2005, 10:04 PM
Pretty much if you threw it at enormous speed it would go through the earth, but while doing so, the friction between the ball and the air would make it catch fire. It'd pop out in China, where they would eat it like chow mein(or however that's spelled).

AdamLAN
02-13-2005, 10:56 AM
Oh i wish i could understand it as well as you do...i'm better with general relativity.

What does this have to do with technology anyway?

Brain Cell
02-13-2005, 11:08 AM
the solution is simple: make the hole bigger or the ball smaller.
man .. i love the way you think , just like i do :D