Eureka! The Archimedes Principle is about density and buoyancy, but this is one section of the book where the demonstrations did not look promising. Based on the illustrations, it looked like the water would flow over the top and just run down the sides of the glass rather than collecting in the pie plate. Maybe if I used a cup with a rim wider than the base it would work.
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I thought about getting a set of
density blocks for a demonstration but in the end I decided to use computer simulations instead. Both ExploreLearning and Adaptive Curriculum have several great simulations covering density and buoyancy. PhET has one for
buoyancy and another for
density that are free, as is the
Floating Lab.
You could also read Archimedes and the Door of Science by Jeanne Bendick along with the first chapter of this book. The details of what happened when Archimedes figured out the principle named after him are in it as well as Fleisher's book.