SYSTEMS OF UNITS AND CONVERSION TABLES
ARNOLD ENGINEERING DEVELOPMENT CENTER ARNOLD AFB TN
Pagination or Media Count:
Some fundamental concepts of units, dimensions, and physical measurements are discussed, and illustrations of the misunderstandings that exist in the literature concerning these concepts are given. The differences between measure and physical equations are outlined, and a simple example is considered. The choice of how many and which units to use as basic is shown to be completely arbitrary, and the choice is usually made to produce maximum accuracy and convenience. Various mechanical, thermal, and electrical systems of units in common use today are presented, and an engineering ft-lbf-ampsec system is developed to describe electromagnetic problems. The history of some important physical units is traced, and the latest definitions of these units are used to obtain convenient conversion tables for various physical quantities.
- Information Science