Thread: Surface area of a calotte-shape
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Old June 29th, 2009, 04:04 PM
HallsofIvy HallsofIvy is offline
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For "small d\phi", you can ignore the "curvature" of the sphere: that is a cylinder. Its area is the area of the rectangle you get by "unfolding" it. It is a rectangle with height d\phi and width equal to the circumference of the circle, 2\pi times the radius = 2\pi r sin \phi.
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