CPM Homework Help : APCALC Problem 1-23

A semi-circular flag is shown attached to a “pole” at right.

Horizontal segment, with semicircle, with it's diameter centered on the segment, distance across semi circle labeled 6.

Imagine rotating the flag about its pole and describe the resulting three-dimensional figure. Draw a picture of this figure on your paper.
Hint (a):
You can build a model of a rotating flag problem. All you need is a pencil, scissors, tape and some paper. To build your model, cut out a flag and tape it to a pencil (which represents the flagpole). Once assembled, spin the pencil rapidly between your hands. If you spin the pencil fast enough, you will see a 3D figure. In this case, it will be a sphere.

Calculate the volume of the rotated flag.
Hint (b):
$\text{volume of a sphere}=\frac{4}{3}\pi r^3$
More Help (b):
Be careful! The radius of this sphere is not $6$ .

Use the eTool below to visualize the flag.
Click the link at right for the full version of the eTool: Calc 1-23 HW eTool