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# Approximations

5 replies to this topic

### #1 Yoruichi-san

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Posted 21 September 2012 - 11:08 PM

(Okay yes, this was inspired by an xkcd comic...)

Find the most accurate approximation (for the the units given) that has 5 characters or less (not counting negative sign or decimal point) for the following:

1) Gravitational constant: 6.673x10^-11 (m^3/kg/s)
3) Planck's constant: 6.026x10^-34 (m^2*kg/s)
4) Electron mass: 9.109x10^-31 (kg)
5) Boltzmann constant: 8.617x10^-5 (eV/K)
6) Permittivity of free space: 8.854x10^-12 (F/m)
7) Elementary charge: 1.602x10^-19 C

I.e. you could approximate a light-year as 99^8 (m).
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### #2 phil1882

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Posted 22 September 2012 - 10:24 PM

Spoiler for

Edited by phil1882, 22 September 2012 - 10:26 PM.

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### #3 Yoruichi-san

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Posted 23 September 2012 - 03:41 AM

That's pretty good. In case my example confused anyone, you can also use things besides exponents (including operators), and you can use non-integers in exponents. Heck, go ahead and throw in pi (it can count as one character) and e if you want for fun .
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Women are definitely stronger. We are [Fe]males, after all...

Some of what makes me me is real, some of what makes me me is imaginary...I guess I'm just complex. ;P

<3 BBC's Sherlock, the series and the man. "Smart is the new sexy."

Chromatic Witch links now on my 'About Me' page! Episode 3 is finally here!

When life hands me lemons, I make invisible ink.

### #4 James33

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Posted 24 September 2012 - 06:30 PM

May be cheating but Avogadro's constant=R/K
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### #5 Rob_Gandy

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Posted 24 September 2012 - 07:56 PM

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### #6 Rob_Gandy

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Posted 26 September 2012 - 06:42 PM

I came up with some others.
Spoiler for Approx.

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