SOLUTION: a rectangle with 4cm and 10cm is revolved about its longer side,find the volume and surface area

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Question 992735: a rectangle with 4cm and 10cm is revolved about its longer side,find the volume and surface area
Answer by Alan3354(69443) About Me  (Show Source):
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a rectangle with 4cm and 10cm is revolved about its longer side,find the volume and surface area
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Area = 4*10 = 40 cm^2
The centroid is 2 cm from the axis of rotation.
Theorem of Pappus --> Vol = 40*2*2pi = 160pi cubic cm.
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The lateral area is that of a cylinder with r = 10 cm and h = 4 cm