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Circle with square cross sections

  1. Sep 9, 2009 #1
    1. The problem statement, all variables and given/known data

    The base of S is a circular disk with radius 2r. Parallel cross-sections perpendicular to the base are squares.
    Find the volume V of this solid.

    2. Relevant equations

    3. The attempt at a solution

    I'm clueless
  2. jcsd
  3. Sep 9, 2009 #2


    Staff: Mentor

    Draw a sketch of the 3D solid in this way.
    Draw a circle of radius 2r (so diameter is 4r), with its center at (0, 0).
    Draw several line segments across the circle, and parallel to the x-axis from one side to another. For each of these line segments, draw a square whose height is equal to its width. If you think about it, the maximum square will be on the x-axis, and the sizes of the squares taper off as you go up or down the y-axis.
    Does that help?
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