When sand particles are put into motion, heavy and light objects will sink or float in the sand and behave just like in a fluid. The moving sand can be used to demonstrate the concept of buoyant forces. However, due to the size and friction of the sand particles the buoyant force does not quite equal the weight of the amount of sand displaced by the submerged objects (Archimedes principle).
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Homemade science is a collection of classroom tested ideas, suggestions, projects, and experiments that I have used in teaching physical science for the Annville-Cleona school district in central Pennsylvania. I am currently in my 38th year of teaching. My intention is to share these ideas with other teachers or anyone who has an interest in science. I have found that designing and building my own equipment has taught me more than any course that I have ever taken. I hope that you consider making or trying these experiements for yourself.