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-   -   Just for fun... Help Zeus measure his band (https://www.askmehelpdesk.com/showthread.php?t=51582)

  • Jan 1, 2007, 02:59 PM
    Fianchetto
    Just for fun... Help Zeus measure his band
    I, the somewhat mighty and moderately powerful Zeus decided to improve on that Other Guy's work by making the globe of the Earth a perfect sphere. I then hired a sub-contractor named Moses to part the resultant global ocean at the equator to form two great seas, leaving dry land between. I saw then an image of Saturn from the Cassini probe and thought it would be jolly nice to have a band about the Earth. So, I put a band of silver upon the surface of the Earth, at the equator, Moses having given me plenty of room to work. I saw the pics of Saturn again and realised that its rings were of larger diameter than the planet. So, I increased the length of my band by 3 inches. Now the band hovers above the surface of the planet by some amount. I wish to measure its altitude - but which instrument would best suit my needs?

    a> an interferometer
    b> a micrometer
    c> a ruler
    d> an altimeter

    :confused: :confused: :confused:
  • Jan 1, 2007, 03:01 PM
    s2tp
    Uh wild guess... Altimeter?
  • Jan 1, 2007, 03:13 PM
    Capuchin
    A ruler - or a micrometer if you wanted to be accurate? :p
  • Jan 1, 2007, 03:16 PM
    s2tp
    Hehe the only reason I guessed it is cause I know I am always giving the pilots the Altimeter so they can monitor their altitude... so I guess its not too wild of a guess... hehe

    (I am an Air Traffic Controller)
  • Jan 1, 2007, 03:19 PM
    TheSavage
    A micrometer is used for thickness -- lets go with the simple good old ruler.
  • Jan 1, 2007, 03:20 PM
    Fianchetto
    Quote:

    Originally Posted by Capuchin
    a ruler - or a micrometer if you wanted to be accurate? :p

    Zeus says there should be a mathematical explanation for your answer, should he acquire more length of silver band to amend to the current one.
  • Jan 1, 2007, 03:28 PM
    Fianchetto
    Quote:

    Originally Posted by s2tp
    hehe the only reason I guessed it is cause I know I am always giving the pilots the Altimeter so they can monitor their altitude...so I guess its not too wild of a guess...hehe

    (I am an Air Traffic Controller)


    The key is to determine what distance is involved and to select the appropriate instrument -

    Interferometer - millionths of inch
    (inside) micrometer - thousandths of an inch
    Ruler - inches to ~ hundredths of an inch
    Altimeter - feet
  • Jan 1, 2007, 03:31 PM
    s2tp
    Looked up my answer and got some definitions;

    Altimeter: An instrument used to measure the height above sea level. An instrument that indicates the altitude of an object above a fixed level. Pressure altimeters use an aneroid barometer with a scale graduated in altitude instead of pressure.

    Interferometer:An instrument that employs the interference of light waves to measure the wavefront.

    Micrometer: a metric unit of linear measurement equivalent to one-thousandth of a millimeter or one-millionth of a meter, it is the common dimension used to measure the length of glochidia and juvenile mussels

    Ruler:A ruler is an instrument used in geometry to measure short/medium distances and/or to rule straight lines.


    OK so I stand by my original answer... altimeter :) I actually learned stuff by searching all that.. yay me, today is a success... haha
  • Jan 1, 2007, 03:32 PM
    s2tp
    Aaah OK, got it, thanks Fianchetto
  • Jan 1, 2007, 03:44 PM
    Fianchetto
    Quote:

    Originally Posted by s2tp
    aaah ok, got it, thanks Fianchetto


    EXCELLENT! Its an arithmatic problem, not a logic puzzle!
  • Jan 1, 2007, 03:52 PM
    s2tp
    Haha well arithmetic has always been a struggle for me... that word just makes the hair on my neck stand up... haha OK I also struggle with chronic exaggeration.. :p
  • Jan 1, 2007, 04:05 PM
    Fianchetto
    I, the somewhat mighty and moderately powerful Zeus, being to some degree superior to you mere mortals, have done the math (better than you, of course) and being fairly generous, deliver unto you this Hint: No matter how big the original band, increasing the cirumference by 3" will ALWAYS result in the SAME change to the radius.
  • Jan 1, 2007, 10:24 PM
    Fianchetto
    Since you mortals are obviously not up to the challenge, I, the somewhat mighty and moderately powerful Zeus, have chosen to perhaps reveal the answer and its rationale to you in a day or two.. IF , that is, I deem you worthy to know the secrets of the gods. Bwahahahhahahahh! <<<add background llightning and thunder cracks for effect HERE>>>
  • Jan 2, 2007, 12:43 AM
    Capuchin
    3 / 2pi = 0.5 inches ish. That's how I got my answer before...

    I know I did this some years ago with a physics teacher - and the answer was surprising - but now I find it utterly obvious

    Maybe science has broken me in

    Edit - okay I suppose it is surprising that no matter the diameter of the ball, the same increase of radius will happen, but I still find that obvious. I am a slave to science :(
  • Jan 2, 2007, 02:14 AM
    Fianchetto
    Quote:

    Originally Posted by Capuchin
    3 / 2pi = 0.5 inches ish. that's how i got my answer before...

    I know I did this some years ago with a physics teacher - and the answer was suprising - but now I find it utterly obvious

    Maybe science has broken me in

    Edit - okay I suppose it is suprising that no matter the diameter of the ball, the same increase of radius will happen, but I still find that obvious. I am a slave to science :(

    I find the distance of ~.48" obvious, but the fact that it doesn't matter the size of the circle quite surprising...
  • Jan 2, 2007, 02:23 AM
    Capuchin
    I Don't think that your question underlines this, it would have been better to ask how the distance from the surface on a tennis ball compares to the distance from the surface of the earth, upon adding 3inches to the circumference - This would underline that the answer is the same - and I'm sure more people would get it wrong by not running the numbers or thinking about it :)

    The answer is certainly not immediately intuitive :)

    It would be great to have that ring spinning and to use it for transport though ;D
  • Jan 2, 2007, 02:38 AM
    Fianchetto
    Quote:

    Originally Posted by Capuchin
    I Don't think that your question underlines this, it would have been better to ask how the distance from the surface on a tennis ball compares to the distance from the surface of the earth, upon adding 3inches to the circumference - This would underline that the answer is the same - and I'm sure more people would get it wrong by not running the numbers or thinking about it :)

    The answer is certainly not immediately intuitive :)

    Thanks for the critique - I suppose that Zeus could have used a model for himself and allowed his admirers to form the conclusion. :)
  • Jan 2, 2007, 02:49 AM
    Capuchin
    Just a quick question - why Zeus? :p
  • Jan 2, 2007, 05:01 AM
    Fianchetto
    Quote:

    Originally Posted by Capuchin
    Just a quick question - why Zeus? :p

    1> How else better to "compete" with the "Other Guy" and make the joke work?

    2> To avoid the risk of offense to fundamentalist Christians with what might be considered blasphemy (and thus possibly shifting the focus of the question from mathematics to religion).
  • Jan 2, 2007, 05:33 AM
    Capuchin
    Hah, fair enough, It just seems to me that Greek gods were fairly rubbish. Zeus just throws lightning around all day.

    Maybe the titans would have been better for the question, since they created the universe in the Greek mythos.

    Aaannyways, I do agree with avoiding the religious slant.
  • Jan 2, 2007, 05:44 AM
    Fianchetto
    Maybe the titans would have been better for the question, since they created the universe in the Greek mythos.


    I didn't want to create the universe, only modify it to suit my needs, so I hired Zeus. Besides, he came cheap - all I had to do was to find my way out of the labyrinth and correctly answer a couple of riddles.
  • Jan 2, 2007, 05:50 AM
    Capuchin
    I just mean that the Greek gods were never all that powerful - they each seemed rather limited in ability.

    How about Hephaestus? He could have smithed up that ring for you ;)
  • Jan 2, 2007, 05:53 AM
    Curlyben
    Hey why the Greek bias why not Roman or Norse!
    I take offence to the premiss of the Greek Gods being all mighty ;)

    I'd pick a Norse God over any of the Greeks any day.
    Hey no nampy pampy Toga wearing for these guys.
    Full on dead animals and horned helmets all the way.
  • Jan 2, 2007, 05:56 AM
    Capuchin
    Well, for a start the Roman ones were pretty much the same people.
  • Jan 2, 2007, 06:02 AM
    Fianchetto
    Quote:

    Originally Posted by Curlyben
    Hey why the Greek bias why not Roman or Norse!!
    I take offence to the premiss of the Greek Gods being all mighty ;)

    I'd pick a Norse God over any of the Greeks any day.
    Hey no nampy pampy Toga wearing for these guys.
    Full on dead animals and horned helmets all the way.


    OK, Ben, just for you, Next time it's Thor! :D
  • Jan 2, 2007, 06:04 AM
    Capuchin
    I have to disagree, I prefer the raunchy adultery of the Greeks :p
  • Jan 2, 2007, 06:06 AM
    Curlyben
    Hey Cap, what ever rocks your boat.
  • Jan 2, 2007, 06:10 AM
    Capuchin
    ;)
  • Jan 2, 2007, 06:10 AM
    Fianchetto
    So much for avoiding the <ancient> religious debate.:)
  • Jan 2, 2007, 06:13 AM
    Capuchin
    I can understand a bit of ancient greek and latin too, none of that norse rubbish for me.
  • Jan 2, 2007, 06:18 AM
    Curlyben
    Come on the Norse god knew just how to PARTYYYYY.
    Hollowed out skulls of their enemies filled with beer and large amounts of roasted animals to chow on.
    None of the poncy grapes and lutes and whine for these boys ;)
  • Jan 2, 2007, 06:28 AM
    Capuchin
    Lutes are awesome.
  • Jan 6, 2007, 08:00 AM
    Fianchetto
    Quote:

    Originally Posted by Fianchetto
    I, the somewhat mighty and moderately powerful Zeus decided to improve on that Other Guy's work by making the globe of the Earth a perfect sphere. I then hired a sub-contractor named Moses to part the resultant global ocean at the equator to form two great seas, leaving dry land between. I saw then an image of Saturn from the Cassini probe and thought it would be jolly nice to have a band about the Earth. So, I put a band of silver upon the surface of the Earth, at the equator, Moses having given me plenty of room to work. I saw the pics of Saturn again and realised that its rings were of larger diameter than the planet. So, I increased the length of my band by 3 inches. Now the band hovers above the surface of the planet by some amount. I wish to measure its altitude - but which instrument would best suit my needs?

    a> an interferometer
    b> a micrometer
    c> a ruler
    d> an altimeter

    :confused: :confused: :confused:

    OK, I, the somewhat mighty and moderately powerful Zeus have decided to torture no longer you poor mortals that are ashamed to post a (probably incorrect) solution here to give you all a break.
    It's like this:



    The initial case:

    C1=2*PI*r1

    The "expanded" case:

    C1+3=2*PI*r2

    solving for r1 & r2 we have

    r2=(C1+3)/(2*PI) r1=(C1)/(2*PI)

    r2-r1=

    [(C1+3)-(C1)]/(2*PI)

    =3/(2*PI)=3/6.28= ~.48" ergo a ruler would work fine


    And because the original circumference is always subtracted from itself (=0) it is arbitrary whether the initial band is a million inches, a thousand inches, ten inches, .1 inches, -10 inches - for a given growth in the curcumference, it will always produce the same change in radius no matter what the starting circumference.

    The Chair recognizes Thor to come forth when ready for the next "Just for fun" mathematical conundrum.

    Message delivered by,
    Fianchetto
  • Jan 6, 2007, 08:01 AM
    Capuchin
    Great work Zeus, you show me a -10 inch band and I'll admit you're the king of the gods.

    Since I got it right, does that mean I'm not mortal or what? :P

    It was good fun though, looking forward to Thor's contribution.
  • Jan 6, 2007, 08:18 AM
    Fianchetto
    Quote:

    Originally Posted by Capuchin
    Great work Zeus, you show me a -10 inch band and i'll admit you're the king of the gods.

    Since I got it right, does that mean i'm not mortal or what? :P

    It was good fun though, looking forward to Thor's contribution.


    >> Make me a Klein bottle, fill it with wine, and I'll pour the contents through your -10" band. And we can drink a toast to mathematics or pizza or Italian women or something.:)

    >> You didn't show your work, so I'll confer upon you all the rights and privileges of Demi-god Status in good standing. :)

    >> Shouldm't be to hard to find a problem that he can't solve, it's you guys I'm worried about!:)


    It HAS been quite fun - Thanks for the good-natured banter - I can't give you two reps in a row :(

    Thanks,
    Fianchetto
  • Jan 6, 2007, 08:35 AM
    Capuchin
    Hehehe,

    Well, I posted all the working I needed to do, as I know that the converting to circumference and back is useless. ;)
  • Jan 6, 2007, 09:02 AM
    Fianchetto
    Quote:

    Originally Posted by Capuchin
    hehehe,

    Well, I posted all the working I needed to do, as I know that the converting to circumference and back is useless. ;)

    Yes - for YOU, but what about the kid in the back of the class, whose primary concerns are getting enough dope and alcohol to last the weekend and still having enough left over to get the next tattoo. You might just get through to him and turn him into the next Steve Jobs or Bill Gates.:)

    Fianchetto

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