Kinetic Sand Experience
Pure sand is a mixture of small grains of various rocks (mainly quartz). When the sand gets wet, quartz crystals are attracted to each other due to the forces of the surface tension of water, and therefore rather stable structures can be built from wet sand. When the water evaporates, there are not enough forces fastening the system, and the sand castle collapses.
But the water film covering the particles has a number of disadvantages. In particular, moist grains of sand adhere not only to each other, but also to the skin. And at home on the floor with wet sand you won’t play - there will be dirt, the consequences of the game will creak under your feet. In general, the Swedes from WABAfun offered an original solution.
It's hard to believe, but in these photos the tester holds his hands completely still. Extracted from the form of a lump of sand begins to creep on its own. Between frames - approximately 10-15 seconds."> Test for friability It is difficult to believe, but in these photographs the tester holds his hands motionless. Extracted from the form of a lump of sand begins to creep on its own. Between frames - about 10-15 seconds.
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