By Geoff Berks on November 28, 1997:
How do you work out the curved surface area of a cylinder?
By Giles Byford:
It's a lot easier if you think of the cylinder as a sheet of
paper that's been rolled up into a pipe. Then you can think of the
area of the curved surface as a flat rectangle (which you know how
to obtain the area of).
The things you need are therefore the height and width of the
rectangle. The height is simply the height of the cylinder. The
width needs a little thought back to the original shape. If you
imagine rolling up the paper, then you can see that the width of
the rectangle is just the circumference of the circle, which you
can easily work out.
Giles Byford
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