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A riddle

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Originally posted by: silverpig
Originally posted by: LoKe
Originally posted by: silverpig
Originally posted by: Xionide
Speed of sound. After the cat hit that it could no longer hear the clang and double its speed.

NEXT!
Click to expand...

Say he's going at .9 times the speed of sound. He'll hear the clang, and jump up to 1.8 times the speed of sound.
Click to expand...

:thumbsup:

This riddle loses.
Click to expand...

So my answer wins 🙂

The fastest the cat can go is a little under twice the speed of sound. 😀
Click to expand...

Not necessarily, for it could be any number between 1.00000~1 and 1.9999~
 
Originally posted by: OdiN
Eventually the cat will be running at around 100MPH, which will have sufficient lift on the piece of metal to cause it to remain in midair and not clank anymore.

And at this time....the plane will take off.
Click to expand...

Unless the tracks are on a conveyor system... 😀
 
Originally posted by: silverpig
Originally posted by: LoKe
Originally posted by: silverpig
Originally posted by: Xionide
Speed of sound. After the cat hit that it could no longer hear the clang and double its speed.

NEXT!
Click to expand...

Say he's going at .9 times the speed of sound. He'll hear the clang, and jump up to 1.8 times the speed of sound.
Click to expand...

:thumbsup:

This riddle loses.
Click to expand...

So my answer wins 🙂

The fastest the cat can go is a little under twice the speed of sound. 😀
Click to expand...

Not quite true either.

If the cat happens to be going 50% of the speed of sound, hears a clang and then doubles...then it's exactly the speed of sound.

So the possible solutions are infinite.
 
Originally posted by: OdiN
Originally posted by: narcotic
Originally posted by: Xionide
Speed of sound. After the cat hit that it could no longer hear the clang and double its speed.

NEXT!
Click to expand...

FTW
care to explain...?

Edit: didn't see you explained that...
Click to expand...

Not quite true.

If the cat was going at 99.9% of the speed of sound, then heard the clank, it would then double it's speed and be going much faster than the speed of sound.

So in order to solve the problem you need to be given a starting speed and a way to calculate how much time passes between each "clank", etc.
Click to expand...

You are correct in that, there's no accurate solution without a given initial speed.
Yet in this riddle, what matters was to get the point that once you travel faster than sound, you won't hear any sound.
So in this case any answer between speed of sound + epsilon to 2*(speed of sound - epsilon) is correct.

 
Originally posted by: narcotic
Originally posted by: Xionide
Speed of sound. After the cat hit that it could no longer hear the clang and double its speed.

NEXT!
Click to expand...

FTW
care to explain...?

Edit: didn't see you explained that...
Click to expand...

That's stupid...I was doing this in a theoretical world where the cat hears it immediately. Putting read world limitations on a problem that has an "infinite rail" and a cat that can run at an "infinite speed" is just way too stupid.
 
Originally posted by: OdiN
Originally posted by: silverpig
Originally posted by: LoKe
Originally posted by: silverpig
Originally posted by: Xionide
Speed of sound. After the cat hit that it could no longer hear the clang and double its speed.

NEXT!
Click to expand...

Say he's going at .9 times the speed of sound. He'll hear the clang, and jump up to 1.8 times the speed of sound.
Click to expand...

:thumbsup:

This riddle loses.
Click to expand...

So my answer wins 🙂

The fastest the cat can go is a little under twice the speed of sound. 😀
Click to expand...

Not quite true either.

If the cat happens to be going 50% of the speed of sound, hears a clang and then doubles...then it's exactly the speed of sound.

So the possible solutions are infinite.
Click to expand...

Nope...if the cat is going .99X the speed of sound it will still hear it and double it's speed to 1.98X the speed of sound.
 
anywhere from 1 times the speed of sound all the way to 1.999x the speed of sound depending on initial starting speed.

this one wasn't very hard.
 
Originally posted by: HeroOfPellinor
Originally posted by: OdiN
Originally posted by: silverpig
Originally posted by: LoKe
Originally posted by: silverpig
Originally posted by: Xionide
Speed of sound. After the cat hit that it could no longer hear the clang and double its speed.

NEXT!
Click to expand...

Say he's going at .9 times the speed of sound. He'll hear the clang, and jump up to 1.8 times the speed of sound.
Click to expand...

:thumbsup:

This riddle loses.
Click to expand...

So my answer wins 🙂

The fastest the cat can go is a little under twice the speed of sound. 😀
Click to expand...

Not quite true either.

If the cat happens to be going 50% of the speed of sound, hears a clang and then doubles...then it's exactly the speed of sound.

So the possible solutions are infinite.
Click to expand...

Nope...if the cat is going .99X the speed of sound it will still hear it and double it's speed to 1.98X the speed of sound.
Click to expand...

He's saying if the cat gets up to .50 times the speed of sound, he'll double and be a 1times the speed of sound.
 
Well, we can note here that we used the sound speed as variable which can fit to any location. We never gave any specific/constant assignment to that variable, thus it will hold true under any physical condition (except for one where no sound can be heard, but then its arguable that the speed of sound in that case is 0, thus the cat would travel in 0 < speed < epsilon and our assumption holds).
 
Originally posted by: narcotic
Well, we can note here that we used the sound speed as variable which can fit to any location. We never gave any specific/constant assignment to that variable, thus it will hold true under any physical condition (except for one where no sound can be heard, but then its arguable that the speed of sound in that case is 0, thus the cat would travel in 0 < speed < epsilon and our assumption holds).
Click to expand...

No. The riddle is flawed, no matter how hard you try to prove it.
 
if the cat is running ON the rail, and is towing a piece of steel, it would constantly be riding on the rail too, and hence never clang, and the cat would continue running at the speed at which it started
 
Originally posted by: Howard
c <= v < 2c

where c is the speed of sound
Click to expand...

^ That, unless the cat's initial speed is greater than c, if that is so, then the cat will not speed up and will instead maintain its inital speed.

This riddle sucks.
 
Originally posted by: ssvegeta1010
Originally posted by: Howard
c <= v < 2c

where c is the speed of sound
Click to expand...

^ That, unless the cat's initial speed is greater than c, if that is so, then the cat will not speed up and will instead maintain its inital speed.

This riddle sucks.
Click to expand...

What do you mean "unless"?

The speed would still be greater than or equal to C, and less than 2c.
 
Originally posted by: ssvegeta1010
Originally posted by: Howard
c <= v < 2c

where c is the speed of sound
Click to expand...

^ That, unless the cat's initial speed is greater than c, if that is so, then the cat will not speed up and will instead maintain its inital speed.

This riddle sucks.
Click to expand...

Yep, thanks for letting us know how you feel, we feel the same way about you. :cookie:

Next...
 
Originally posted by: BigJ
Originally posted by: ssvegeta1010
Originally posted by: Howard
c <= v < 2c

where c is the speed of sound
Click to expand...

^ That, unless the cat's initial speed is greater than c, if that is so, then the cat will not speed up and will instead maintain its inital speed.

This riddle sucks.
Click to expand...

What do you mean "unless"?

The speed would still be greater than or equal to C, and less than 2c.
Click to expand...

If the cat started at 80 times the speed of sound, it wouldn't slow down to below twice the speed of sound, now would it?
 
Originally posted by: JujuFish
Originally posted by: BigJ
Originally posted by: ssvegeta1010
Originally posted by: Howard
c <= v < 2c

where c is the speed of sound
Click to expand...

^ That, unless the cat's initial speed is greater than c, if that is so, then the cat will not speed up and will instead maintain its inital speed.

This riddle sucks.
Click to expand...

What do you mean "unless"?

The speed would still be greater than or equal to C, and less than 2c.
Click to expand...

If the cat started at 80 times the speed of sound, it wouldn't slow down to below twice the speed of sound, now would it?
Click to expand...

Vegeta did not specifically mention greater than 2C, but simply greater than C. His statement in no way supports an initial speed of greater than 2C.

In any case, the complete answer would be

If 0 < Xinitial < C
C <= Xfinal < 2C

If Xinitial >= C
Xinitial = Xfinal
 
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