[mar_mazz (OP)]

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!

[)] Marzia

[neilep]

Isn't it something that you just wouldn't believe...like only fifty times ?...

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

[thefunkyaquarium]

Something like that.

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

[Ultima]

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) [] 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

[neilep]

...amazing...so my guestimate at 50 was pretty darn close  !!

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

[Ultima]

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 []. One thing to think about is bacteria populations grow in a similar manner []

[simeonie]

You lost me at "hi"

[Solvay_1927]

A related link, in case anyone's interested:
http://www.thenakedscientists.com/forum/topic.asp?TOPIC_ID=2946