A dimension is an extension in a particular direction.^{[1]} A line has one dimension, since it extends in only one direction. A two dimensional space has two dimensions. An x-y graph is two dimensional. The x-axis defines one dimension and the y-axis defines another.
A dimension is not necessarily length. A dimension may also be temperature, time, mass, electrical current and others. For example, an equation may relate time and temperature: p = 2.5t where p represents temperature and t represents time. In this equation, one dimension is time and the other dimension is temperature. Albert Einstein's special theory of relativity deals with four dimensions: three dimensions are lengths making up a space, and one dimension is time. See also Dimensional Analysis.
An object is said to be dimensionless if it has no dimensions. The only object in most geometries that is dimensionless is a point.
Number Dimensions | Manipulative | Description |
---|---|---|
0 | A point has no dimensions. | |
1-D 1 dimensional | A line has one dimension. | |
2-D 2 dimensional | A two-variable Cartesian coordinate system has two dimensions. | |
A rectangle has two dimensions (length and width). | ||
A circle has two dimensions (length and width). | ||
3-D 3 dimensional | A sphere has three dimensions (length, width, and height). | |
A rectangular solid has three dimensions (length, width, and height). | ||
4-D 4 dimensional | Euclidean space has four dimensions (length, width, height, and time). | |
Table 1: Dimensions |
# | A | B | C | D |
E | F | G | H | I |
J | K | L | M | N |
O | P | Q | R | S |
T | U | V | W | X |
Y | Z |
All Math Words Encyclopedia is a service of
Life is a Story Problem LLC.
Copyright © 2005-2011 Life is a Story Problem LLC. All rights reserved.
This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 License