Well, not the maths as such, but the principle.
I have spent many a long hour over the last couple of years chucking stuff into a concrete mixer, and I am constantly puzzled as to why the stuff I tip back out again is uniformly mixed. This has come to a head in the last few days when I have been mixing screed, which is a sand and cement mix, only damp, but with an entirely different type of product added.......fibreglass strands. You tease these apart and add about a hand-full per mixer-full. For the life of me I cannot understand why they should be evenly distributed throughout the rest of the mixture no matter whether you leave it mixing for 2 minutes or 45 minutes. Why isn't this about randomising, rather than evenly mixing?
Random distributions seldom produce an even spread, as we know. So things which are randomly distributed appear to be clustered here and there, and sparsely spread elsewhere. Why doesn't that happen with the fibreglass in my screed? (For that matter, why doesn't it happen with the pumpkin seeds in my bread dough when I mix that in a food mixer?) I can understand that the chemistry of mixing just the sand, cement and water would likely make the mixture even (the tiny cement particles fill the gaps between the much larger sand particles)...........but how is it that I haven't found globs of balled-up fibres in my mix?
I have spent many a long hour over the last couple of years chucking stuff into a concrete mixer, and I am constantly puzzled as to why the stuff I tip back out again is uniformly mixed. This has come to a head in the last few days when I have been mixing screed, which is a sand and cement mix, only damp, but with an entirely different type of product added.......fibreglass strands. You tease these apart and add about a hand-full per mixer-full. For the life of me I cannot understand why they should be evenly distributed throughout the rest of the mixture no matter whether you leave it mixing for 2 minutes or 45 minutes. Why isn't this about randomising, rather than evenly mixing?
Random distributions seldom produce an even spread, as we know. So things which are randomly distributed appear to be clustered here and there, and sparsely spread elsewhere. Why doesn't that happen with the fibreglass in my screed? (For that matter, why doesn't it happen with the pumpkin seeds in my bread dough when I mix that in a food mixer?) I can understand that the chemistry of mixing just the sand, cement and water would likely make the mixture even (the tiny cement particles fill the gaps between the much larger sand particles)...........but how is it that I haven't found globs of balled-up fibres in my mix?
via International Skeptics Forum http://ift.tt/2h3mel7
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