- #1
Ryker
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Hey, so I guess my question is as follows. I've got a problem picturing a pyramid only being Bh/3 and not Bh/2. I've looked at the proof why it is so, and it seems reasonable when looking at it, BUT if I imagine a cone vs. a cylinder sliced with vertical rather than horizontal cuts I'm lost. See, you get a cylinder if you rotate a rectangle, but you get a cone with the same height if you rotate a triangle whose area is half of that of a rectangle. And if I then imagine the cone and cylinder sliced vertically to slices of virtually zero width (z component, as opposed to height and radius of the underlying circle) I get an indefinite number of them shaped as either rectangles with area x or triangles with an area of x/2.
So I guess what I wanted to ask is what am I missing. Because if my thinking as presented above was true, the volume of the cone vs. the cylinder would have a ratio of a half and not a third. Where is the rest of the cylinder and why is it not covered in the said image of an indefinite number of rectangles vs. triangles?
Thanks in advance.
So I guess what I wanted to ask is what am I missing. Because if my thinking as presented above was true, the volume of the cone vs. the cylinder would have a ratio of a half and not a third. Where is the rest of the cylinder and why is it not covered in the said image of an indefinite number of rectangles vs. triangles?
Thanks in advance.