Associated Topics || Dr. Math Home || Search Dr. Math

### Dimensions

```
Date: 08/30/2001 at 20:52:22
From: Emily
Subject: Dimension

What are 1-dimensional, 2-dimensional, and 3-dimensional? What's the
difference?
```

```
Date: 08/30/2001 at 23:02:40
From: Doctor Peterson
Subject: Re: Dimension

Hi, Emily.

Essentially, an N-dimensional object is one that requires N numbers to
describe a location in it.

A line is 1-dimensional, since one number, the distance from zero,
tells you where you are.

A plane is 2-dimensional, since you need x and y to locate a point.

A circle (the curve itself, not the interior of it) is a 1-dimensional
object in a 2-dimensional space, since although it takes 2 numbers to
identify where in the plane a point on the circle is, only one number
(the angle from a starting position) tells you where you are as long
as you know you are on the circle.

For 3 dimensions, here is a discussion I found in our archives:

Is a Sphere 2-D or 3-D?
http://mathforum.org/dr.math/problems/janice.8.8.96.html

- Doctor Peterson, The Math Forum
http://mathforum.org/dr.math/
```
Associated Topics:
High School Definitions
High School Euclidean/Plane Geometry
High School Geometry
High School Higher-Dimensional Geometry
Middle School Definitions
Middle School Geometry
Middle School Higher-Dimensional Geometry
Middle School Two-Dimensional Geometry

Search the Dr. Math Library:

 Find items containing (put spaces between keywords):   Click only once for faster results: [ Choose "whole words" when searching for a word like age.] all keywords, in any order at least one, that exact phrase parts of words whole words

Submit your own question to Dr. Math
Math Forum Home || Math Library || Quick Reference || Math Forum Search