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Topic: A4 Paper Size (Read 663 times) |
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Barukh
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A4 Paper Size
« on: Oct 19th, 2004, 2:07am » |
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A friend of mine asked recently the following simple question: Why the dimensions of the A4 Paper format are what they are? I didn't know the answer - until he told me.
Do you know the answer?
May be, you have other questions of that kind?
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towr
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Re: A4 Paper Size
« Reply #1 on: Oct 19th, 2004, 3:57am » |
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The ratio between the sides is 1 to sqrt(2)
This means that if you fold it in half, the ratio remains the same. And that's all sorts of wonderful. If you have an A3, you can make 2 A4's out of it, or vice versa: f.i. print an A3 image on 2 A4's and put those together.
That covers the relation between width and height. The absolute values depend on the area, and again it makes perfect sense:
A4 = 0.0625 m2
A3 = 0.125 m2
A2 = 0.25 m2
A1 = 0.5 m2
A0 = 1 m2
So an An size paper has area 1/2n, and since weight of paper is given per area-unit, this makes it easy to calculate.
an A4 of 80 gr/m2 paper weighs 1/16th of 80 gr = 5 gr
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| « Last Edit: Oct 19th, 2004, 3:58am by towr » |
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Grimbal
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Re: A4 Paper Size
« Reply #2 on: Oct 19th, 2004, 10:28am » |
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So the answer would be sqrt(sqrt(2))/4 m and 1/sqrt(2) times that, that is 29.7 cm x 21.0 cm.
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towr
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Re: A4 Paper Size
« Reply #3 on: Oct 19th, 2004, 12:42pm » |
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That's an answer to the question of what the dimensions are, not to why they are what they are.
Of course metaphysically speaking, they are what they are because if they were not, they would be what they aren't, which is a contradiction. So they have to be what they are because they cannot be anything else.
hmm is that assuming they are in the first place?
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Sir Col
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Re: A4 Paper Size
« Reply #4 on: Oct 20th, 2004, 12:58am » |
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And of course, your deductive reasoning depends on the state of being and not being, being mutually exlusive, as opposed to existence of some state in-between. Whether or not something can be between being and not being depends on being sure that being and not being exist as mutually exlusive entities and the certainty that things that are, are what they are. As we cannot be sure of this, the state of in-betweenness must be a potential of all things. Perhaps it IS the state of all things?
By the way, nice expo on the family of An papers, towr.
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