Chapter 10, Archimedes and the Centers of Gravity Summary and Analysis

Much is still unknown about gravity, but most of what we know came from Sir Isaac Newton in the 17th Century. But Greek scientists worked on gravity in their day. Archimedes thought a lot about balance and centers of gravity. When he demonstrated the idea of centers of gravity, he laid the groundwork for theoretical mechanics. An object's center of gravity is the point where an object's weight seems to center.

Archimedes wrote books on mechanics showing that centers of gravity are not always located at the centers of objects. Not everything balances in the middle. He found that weights that balance one another at equal distances have equal weight. This helps to make sense of the relationship between planets, starts and moons. The center of gravity of the...