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Author Topic: A piece of paper can take you to the Moon!  (Read 7713 times)

Offline mar_mazz

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A piece of paper can take you to the Moon!
« on: 19/10/2005 09:18:00 »
Hi guys!

Does anyone know how many times I should fold a piece of paper (hei, I mean a NORMAL piece of paper, A4 size)... to cover the distance between Earth and the Moon?

have fun!

[:o)] Marzia


 

Offline neilep

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Re: A piece of paper can take you to the Moon!
« Reply #1 on: 19/10/2005 13:44:43 »
Isn't it something that you just wouldn't believe...like only fifty times ?...

Men are the same as women.... just inside out !!
 

Offline thefunkyaquarium

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Re: A piece of paper can take you to the Moon!
« Reply #2 on: 19/10/2005 22:47:32 »
Something like that.

Except it's actually impossible to fold a piece of paper in half more than about 8 times.
 

Offline Ultima

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Re: A piece of paper can take you to the Moon!
« Reply #3 on: 22/10/2005 17:15:32 »
There's a set limit to how many times you can fold a piece of paper regardless of size or the type of paper (or anything) :D So the answer is you can't. If you wanted to work it out in theory, then the thickness of the paper doubles with every fold. Say the paper is a tenth of a millimeter thick. 0.00001m and the average distance to the moon is 382,500,000m..

Since im a computery person here you go:

Code: [Select]

#include <stdio.h>
#include <stdlib.h>

#define papthck 0.00001
#define moondst 382500000.0

/**
 *   getfolds.c
 *
 * Lets work out the paper folds to some distance!
 * Default to the number of folds to the MOON.
 *   Ultima (2005-10-22)
 * */

long getfolds (double start, double end);

/*
 * 1st arg thickness of material, followed by distance to reach.
 */
int main (argc, argv)
int argc;
char **argv;
{
   if (argc == 1) {
      printf("No. of paper folds to MOON: %ld\n",getfolds(papthck,moondst));
   }
   else {
      printf("No. of folds: %ld\n",getfolds(atof(argv[1]),atof(argv[2])));
   }
return EXIT_SUCCESS;
}

/*
 * Get that sassy value you want.
 */
long getfolds (start, end)
double start;
double end;
{
static long number = 0;
   if (start >= end) return number;
   start *= 2;
   number ++;
   getfolds(start, end);
return number;
}

The answer is 46 give or take a fold ;)

http://mathworld.wolfram.com/Folding.html
« Last Edit: 22/10/2005 20:00:41 by Ultima »
 

Offline neilep

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Re: A piece of paper can take you to the Moon!
« Reply #4 on: 22/10/2005 20:51:06 »
...amazing...so my guestimate at 50 was pretty darn close  !!

Men are the same as women.... just inside out !!
 

Offline Ultima

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Re: A piece of paper can take you to the Moon!
« Reply #5 on: 23/10/2005 00:45:29 »
Well that depends what you mean by close :) it would be 2^4 x <distance to the moon> out.
I was surprised it was so little and I know what exponential growth is like from programming :D. One thing to think about is bacteria populations grow in a similar manner ;)
 

Offline simeonie

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Re: A piece of paper can take you to the Moon!
« Reply #6 on: 14/12/2005 17:32:13 »
You lost me at "hi"
« Last Edit: 27/06/2009 15:15:03 by BenV »
 

Offline Solvay_1927

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Re: A piece of paper can take you to the Moon!
« Reply #7 on: 14/12/2005 23:58:52 »
A related link, in case anyone's interested:
http://www.thenakedscientists.com/forum/topic.asp?TOPIC_ID=2946
 

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Re: A piece of paper can take you to the Moon!
« Reply #7 on: 14/12/2005 23:58:52 »

 

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