The Second Theorem
The second theorem states that the volume V of a solid of revolution generated by rotating a plane figure F about an external axis is equal to the product of the area A of F and the distance d traveled by its geometric centroid.
For example, the volume of the torus with minor radius r and major radius R is
Read more about this topic: Pappus's Centroid Theorem
Famous quotes containing the words the second and/or theorem:
“Two principles, according to the Settembrinian cosmogony, were in perpetual conflict for possession of the world: force and justice, tyranny and freedom, superstition and knowledge; the law of permanence and the law of change, of ceaseless fermentation issuing in progress. One might call the first the Asiatic, the second the European principle.”
—Thomas Mann (1875–1955)
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—Albert Camus (1913–1960)