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hyperbolic bowls - make a clay cone - & the angle of the hyperbola

updated fri 31 jan 03


Philip Poburka on thu 30 jan 03

verses a Parabola

Hello Michael,

What a good idea! - to make the Cones of Clay and cut

However, I think the Hyperbola is 90 degrees to the plane of
the base...whilst the Parabola is some angle other than
90...without it mattters much what the angle of the sides
are of the Cone in question.

So the larger the ratio of height to width of base, the more
nearly acute the Hyperbola would be...the smaller that
ratio, the more obtuse...

Las Vegas

----- Original Message -----
From: "Michael McDowell"
Sent: Wednesday, January 29, 2003 11:00 PM
Subject: Hyperbolic Bowls


What about doing it in three dimensions out of clay? You
could make
some small cones with different angles for the sides easily
out of clay on the wheel. Then you could slice them when
they are
leather hard and get a pretty good conic section. My
dictionary says
that a hyperbolic curve results from slicing at a greater
angle than
the sides make with the base. Nothing hard about that.
According to
Paul's suggestion, get it right at any size and then blow it
up with
a copy machine.

Michael McDowell
Whatcom County, WA

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