It is, indeed, cool!
I think I was introduced to it there in my first physics
final, which had a bunch of one-point questions, such as these
two, intended to encourage you to think in metric:
1. Assume the speed of light is 186,000 miles per second. Compute
the speed of light in furlongs per fortnight.
2. Assume the speed of light is 300,000 kilometers per second,
and that there are π×10^7 seconds in a year. Compute the
distance light travels in a year.*
I don't recognize the other integer.
Bob
* I don't recall if the answer "one light year" was acceptable or not!
On 13-05-01 02:30 PM, Roger Hui wrote:
Hey man, I didn't say it was original with me, just that it was cool!
Do you recognize this: 142857. (Hint: probably too low brow for a Cal
Techie.)
On Wed, May 1, 2013 at 10:59 AM, Robert Bernecky
<[email protected]>wrote:
The pi*10^7 seconds stuff was a standard back-of-the-envelope
estimate at Caltech in 1964. [And likely much earlier...]
Bob
On 13-05-01 01:05 PM, Roger Hui wrote:
Très cool. https://xkcd.com/1047/ says that 75^4 is approximately the
number of seconds in a year.
y=: */ 365.2425 24 60 60
y
3.1557e7
75^4
3.16406e7
o. 1e7
3.14159e7
y %~ 75^4
1.00265
y %~ o. 1e7
0.995531
So it's not quite as good an estimate, but to say "there are approximately
π times 1e7 seconds in a year", how cool is that?
On Wed, May 1, 2013 at 7:49 AM, Raul Miller<[email protected]>
wrote:
This looks like fun:
http://www.johndcook.com/blog/**2013/04/30/recognizing-**numbers/<http://www.johndcook.com/blog/2013/04/30/recognizing-numbers/>
And perhaps interesting to implement something similar in J (perhaps
based on an enumeration of J's constant language).
--
Raul
------------------------------**------------------------------**
----------
For information about J forums see
http://www.jsoftware.com/**forums.htm<http://www.jsoftware.com/forums.htm>
------------------------------**------------------------------**
----------
For information about J forums see
http://www.jsoftware.com/**forums.htm<http://www.jsoftware.com/forums.htm>
----------------------------------------------------------------------
For information about J forums see http://www.jsoftware.com/forums.htm
----------------------------------------------------------------------
For information about J forums see http://www.jsoftware.com/forums.htm
