I calculated this exact same thing using kitchen salt instead of sand. I actually measured out a small volume of salt and counted 1000 grains. The density came out to be about 350,000 grains per cubic inch or, very naively, equivalent to little cubes 1/70 inch on a side filling space. Sand varies much more than ordinary kitchen salt--for example the beach sand here in Santa Monica is somewhat finer. Anyway 7*10^22 (also the number of stars I used) would occupy about 800 cubic miles, enough to cover Los Angeles County to a depth of 1000 feet, or almost enough to fill the Grand Canyon. Beaches are interesting because the total length, average width, and average depth are all hard to estimate. Steve Gray On 11/1/2010 10:00 AM, Simon Plouffe wrote:
Hello ,
I read recently that the calculated the approx. amount of stars in the known universe to be 7x10^22, which is according to source, greater than the number of grains of sand in all the deserts and beaches on earth.
Well, this is quite big, but as I was explaining this to some people around me,
is there a known value of the number of grains of sand in let's say 1 cubic meter of sand ? I know some are very small and others are bigger : does someone has an approximate value ? I tried to find without success and also I have no idea on how to calculate this simple value.
Thanks for any answer(!).
source : a certain australian study : http://en.wikipedia.org/wiki/Observable_universe
best regards and have a nice evening.
Simon Plouffe
_______________________________________________ math-fun mailing list math-fun@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/math-fun