Ignorable Coordinate

ignorable coordinate

[ig′nȯr·ə·bəl kō′ȯrd·ən·ət]
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Ignorable Coordinate


a generalized coordinate of a mechanical system that does not appear in the system’s Lagrangian function or other characteristic functions. The presence of ignorable coordinates simplifies the integration of the corresponding differential equations of motion of a mechanical system. For example, if the coordinate q1, does not appear in the Lagrangian function L, the Lagrange equation

takes the form

and immediately yields the integral

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.