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some math twisters?


smacker124

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How come you couldnt just post the text instead of scaning in the printed version.

 

Well, the text is not a .text file or anything. It is a .TEX file, so you wouldn't really be able to see it. I would just save it as a PDF, but i do not have a copy of acrobat where i am, just the reader :P

 

Anyways, so i was stuck with printing and scanning, and it was appearently too much for me to handle, lol. Anyways, sorry for the mess that my incompetance has made, i will try better in the futer *sigh*

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I dont mean to be rude, but your answer is incorrect, my equation which is widley used for sequences gives the correct answer as $3000, not $939.39. That answer confused me!

 

No worries. But if you think it is wrong, then perhaps you could point out my mistake so that i could learn from it? Cool.

 

I can see what you did, divide kelvin by 2

I converted to Farenheight then back :)

(I don`t think there is an actual answer tho?)

 

Well, there is a correct answer and it is fafalone's (-136.575). The easiest way to arrive at this answer is to convert to Kelvin and then divide by two. Why?

 

Well, if you look closer at what is happening if you instead convert to Farienhieht what you find is that you have changed the temperature by 16 degrees. However, the farienhieht scale does not end at 0 degrees. THere are many many more degrees that are negative. Thus saying that the temperature is 32 and dividing by two to get 16 only takes into account the positive temperature. HOwever, there are a whole lotta negative ones that need to be considered as well. So, you need to figure out how many degrees are between 0 degrees F and absolute zereo and figure these in as well.

 

Of course, if you just use the kelvin scale and divide by two then all this work is done for you and you immediately arrive at the correct answer.

 

But great questoin YT! It really helps illuminate why the kelvin scale was invented at all. It really simplyfies calculations and helps to eliminate conceptual mistakes like the one you and wolfson made. But i hope you don't feel bad, i think anyone that has worked in science before and been caught off gaurd by this very same thing, so you are in good company :D

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Ok in your calculation’s you get n16 (middle number) being $9xx.xx, if you add them all up they won’t add up, the only way you could do that would be to have a higher first term, which is not possible as n16 is suppose to be highest. Take a look at my calculations and try and pinpoint your error. As for temperature calculation the “psychics-wise” answer is yours, “mathematically-wise” YT and I have the correct answer.

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No, your answer is right only in that you correctly calculated the equation you decided to calculated.

 

16F is not "twice as cold as" 0c

 

Faf's Kelvin calc answers the only interpretation of the problem that actually makes any sense.

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well I stated from the outset, I don`t think there is any actual answer (at least not just ONE answer) as the question is open to interpretaion and verbage, effectively, anything multiplied or divided by Zero is pointless. and so to take the question in it`s literal form would be futile.

I agree 100% with fafs answer and I think conversion to farenheight also makes sense. it IS afterall a "trick" question :)

 

just be glad I didn`t ask if Bald men use soap or shampoo :)

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Like I said, there is only one interpretation of the question that makes any sense, and that is the one based on Kelvin.

 

The Farenheit calculation is a completely random one. It has no bearing at all on the heat energy in any system that you can predict based on the scant information in the question.

 

I bet it's shampoo.

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well considering we CANT we work with Zero (I think we agree on that).

then it would be logical to convert it`s measurement to an equialent sytem (in this case Farenheight) and work from there as it does give us a whole number. THEN do the calc from that side and convert back :)

 

there is no correct answer by virtue of the question though, it was designed as such.

Twice as cold WHAT? zero? well we know that doesn`t make any sense :)

 

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No, there is a possible correct answer. And only one possible answer, as nothing else makes sense. The Kelvin answer.

 

By all means express it in Farenheit or Celsius or Joules per cubic barleycorn, but it's still always going to be 135.5K - not some random value on an arbitrarily assigned scale based around the properties of water.

 

If the Kelvin answer is wrong, nothing else can be right.

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I fail to see how you can assert that?

as Zero divided by anything is always Zero :)

the ONLY way you can make the calc work is to introduce a whole number as a factor (and the question never stated you couldn`t).

and so it is ENTIRELY a matter of interpretation :)

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YT, I think sayo is saying that the kelvin answer is the only answer. Sure, you can get an answer in celcius, but that answer can always be converted back to the correct kelvin answer, since kelvin is the standard around which everything rotates.

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I'm basing it around the fact that "cold" is the term given to a lack of heat energy; the heat energy concept being a derivative of what the Kelvin scale measures.

 

Celcius is based around the melting point and boiling point of water, in order to provide an easier and more convenient scale for dealing with the every-day temperatures we are likely to encounter. The increment "1 degree c" is the same as the increment 1K.

 

Farenheit on the other hand shares no such factor with Kelvin and the division of [0c expressed as Farenheit] by two is not representative of the halving of the energy in a system, which is the only sensible way to interpret the phrase "twice as cold".

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Sayonara³ said in post #41 :

You hideous human earth monkey.

 

Hmmm... yeah, whatever Zzzzz....

 

""I know it's a matter of interpretation, that doesn't mean you can ignore basic physics and logic.""

 

then if you KNOW as you stated that it`s entirely down to interpretation, then logic or physics need not apply!

there IS NO singularly correct answer, as you said, it`s interpretation only :)

both means are equaly valid, and yes C and F do share a comonality else there would be no conversion formula, would there?

and if it shares factors with Celcius, then it shares with Kelvin too as a +273 after conversion :)

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YT2095 said in post #44 :

Hmmm... yeah, whatever Zzzzz....

See: "Invader Zim" - Nikelodeon, CBBC, or Kazaa.

 

"I know it's a matter of interpretation, that doesn't mean you can ignore basic physics and logic"

 

then if you KNOW as you stated that it`s entirely down to interpretation, then logic or physics need not apply!

there IS NO singularly correct answer, as you said, it`s interpretation only :)

both means are equaly valid, and yes C and F do share a comonality else there would be no conversion formula, would there?

and if it shares factors with Celcius, then it shares with Kelvin too as a +273 after conversion :)

See: All of my above posts.

 

What the question actually is is open to interpretation. But only one of those interpretations allows a valid calculation using physics principles - any other interpretation is poorly-applied physics, or just makes no sense.

 

"French is based on Latin, and Japanese can be translated to french. Therefore Japanese is related to Latin."

 

:rolleyes:

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anyway, the fact of the matter is this... the only TRUE answer is that the question itself is ilogical and flawed.

there IS no real answer :)

 

0/2=0

 

So you are saying that if the temperature is 0c it can't be twice as cold tomorrow, because the universe will return "Error"?

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well not quite the last little addon you stated no, I`m saying the question itself is fundementaly flawed.

 

it`s a bit the; irrisistable force meets the imovable object arg, what would happen if they ever met... well the answer is simply that the situation can never occur :)

 

it sure SOUNDS good on paper, and most certainly a problem to ponder when there`s nothing on TV, but the fact of the matter is, it`s language versus Science :)

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