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Thread: Hard to believe

  1. #1
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    Hard to believe

    A true scale model of the Eiffel Tower that was 1 foot tall would only weigh as much as a nickel. About 7 grams, about 1/4 ounce.
    The air in a cylinder containing the Eiffel Tower weighs more than the tower itself. The Tower weight is reportedly 9400 tons and air in the cylinder is 11,200 tons at sea level.
    If all the iron in the Tower were melted into a single square bounded by the base of the Tower it would only be 6 cm or about 2 1/2 inches thick
    My three favorite things are the Oxford comma, irony and missed opportunities

    The problem with humanity is: we have paleolithic emotions; medieval institutions; and God-like technology. Edward O. Wilson

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    I always wondered why the Nazis didn't tear it down for scrap iron. Perhaps there wasn't enough to bother.

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    Interesting. Do you know the math to figure the weight of air in the cylinder?

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    That's very impressive basic engineering, when I was an engineering student we did a project challenge where we built a tower from popsicle sticks. The goal was to build the lightest tower that could support a given weight. Looks like the designers of the Eiffel Tower would have been very competitive in that challenge.
    Calculating the weight of air in the cylinder is a 2 step process, first calculate the volume of the cylinder using the formula V= Pi x r x r x h, where r is radius and h is height of cylinder, then calculate the density of air which is dependent on the pressure, temperature and moisture content of the air.



    and no I didn't have all that memorized, I Googled it.

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    Quote Originally Posted by Pat Barry View Post
    Interesting. Do you know the math to figure the weight of air in the cylinder?
    π x r sq x h. Is the formula for volume of a cylinder. The towers base would fit in a circle 296.5 feet. 3.14159 x 296.5 x 296.5 x 1052 = 290,398,777 cubic ft times the weight of a cubic foot of air at sea level of .0807 = 123,435,181 pounds / 2000 = 11,717 tons or thereabouts.
    And yes, Mr. Eiffel wanted to show how a very large structure could be built very lightly using modern material and engineering. Interestingly it was almost demolished in 1909 but was saved only because of the communication antenna installed at the top.
    Last edited by Michael Weber; 02-06-2018 at 4:12 PM.
    My three favorite things are the Oxford comma, irony and missed opportunities

    The problem with humanity is: we have paleolithic emotions; medieval institutions; and God-like technology. Edward O. Wilson

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    Wow, this is all vary impressive, a lot of smart people here. Over in the Neanderthal Haven of SMC there trying to keep a vise from racking maybe some of you could help out over there I'm just kidding

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    Quote Originally Posted by Chet R Parks View Post
    Wow, this is all vary impressive, a lot of smart people here. Over in the Neanderthal Haven of SMC there trying to keep a vise from racking maybe some of you could help out over there I'm just kidding
    in all fairness, I just read those facts and posted it here because it was, well hard to believe. I flunked high school algebra so don't accuse me of being smart. You can talk to Doug though
    Last edited by Michael Weber; 02-06-2018 at 5:01 PM.
    My three favorite things are the Oxford comma, irony and missed opportunities

    The problem with humanity is: we have paleolithic emotions; medieval institutions; and God-like technology. Edward O. Wilson

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    Quote Originally Posted by Michael Weber View Post
    π x r sq x h. Is the formula for volume of a cylinder. The towers base would fit in a circle 296.5 feet. 3.14159 x 296.5 x 296.5 x 1052 = 290,398,777 cubic ft times the weight of a cubic foot of air at sea level of .0807 = 123,435,181 pounds / 2000 = 11,717 tons or thereabouts.
    And yes, Mr. Eiffel wanted to show how a very large structure could be built very lightly using modern material and engineering. Interestingly it was almost demolished in 1909 but was saved only because of the communication antenna installed at the top.
    Crazy, with all that weight above us it surprising we are not all crushed like bugs.

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    Quote Originally Posted by Chet R Parks View Post
    Wow, this is all vary impressive, a lot of smart people here. Over in the Neanderthal Haven of SMC there trying to keep a vise from racking maybe some of you could help out over there I'm just kidding
    They've got plenty of 'experts' over there. LOL

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    Quote Originally Posted by Michael Weber View Post
    ...
    If all the iron in the Tower were melted into a single square bounded by the base of the Tower it would only be 6 cm or about 2 1/2 inches thick
    Incredible. When I stood underneath looking up I was amazed by the size and apparent massiveness of the structural support. The thing is so big it is hard to photograph from the ground. My pitiful little snapshots can't begin to capture the feeling, even when I'm reminded of the scale by the people in the center of the base in the third photo.


    Eiffel_tower_IMG_2790.jpg Eiffel_tower_IMG_2798.jpg Eiffel_tower_IMG_2800.jpg

    JKJ

  11. #11
    It was the tallest structure until the Empire State Building

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    The math comes up with the right answer but you typed in an extra one.

    It should be 23,435,181/2000 and not 123,435,181/2000.
    Last edited by Larry Frank; 02-06-2018 at 7:52 PM.

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    The structural iron in the tower itself weighs 7,300 tons. When you include passenger elevators, mechanical systems, shops, restaurants, bar, antennae the total weight of the structure is approximately 10,100 tons.

    Was the tallest structure until the Chrysler Building.

    https://en.wikipedia.org/wiki/Eiffel_Tower#Design

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    And.....Eiffel designed the structural part of the Statue of Liberty. He was an amazing engineer.

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    Quote Originally Posted by Larry Frank View Post
    The math comes up with the right answer but you typed in an extra one.

    It should be 23,435,181/2000 and not 123,435,181/2000.
    �� Neither a mathematician nor typist be I.
    My three favorite things are the Oxford comma, irony and missed opportunities

    The problem with humanity is: we have paleolithic emotions; medieval institutions; and God-like technology. Edward O. Wilson

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