What is a Torus?
Date: 11/30/1999 at 10:58:11 From: Jennifer Hemmerlein Subject: How can I explain what a torus is? Hi, I am currently researching three-dimensional shapes for a program for children, and I'm having difficulty explaining in plain terms exactly what a torus is. I've looked in the dictionary and at your mathematical explanations of a torus, but is there a good way to describe a torus to a kid? Thanks, Jennifer
Date: 11/30/1999 at 23:08:20 From: Doctor Douglas Subject: Re: how can I explain what a torus is? Hi Ms. Hemmerlein, The way I would explain it to a kid is to imagine a doughnut, or a bagel. Strictly speaking, it is just the surface of the doughnut (i.e. where the powdered sugar is). One interesting property of a torus is that it is a "connected" surface, or a "connected" shape. If you cut through the doughnut with a knife (once), it stays in one piece (assuming you chose the right cut - it's possible to cut it so that it does fall apart). No matter how you cut through an orange (which of course, is a sphere), though, you end up with two pieces. I hope that helps, and please write back if you need a more detailed explanation. - Doctor Douglas, The Math Forum http://mathforum.org/dr.math/
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