# One question regarding moment??

• 04-01-2005
Alexanderbinich
One question regarding moment??
Hi,

I am doing a project which need the semimajor axis value. I only have moment variables: m00,m01,... mu01, mu11.... Any friend can tell me what is the use of the moment variables? And how to use these variables to compute the semimajor axis value? Thanks!

Regards,
Alexander
• 04-01-2005
DougDbug
Physics????
I have a vague memory that this has something to do with physics or dynamics.... You may need some more information from whomever gave you this assignment/task. Do you have a physics or dynamics book? (I don't have one with me.)
• 04-01-2005
CornedBee
Do you mean momentum?
• 04-01-2005
7stud
Quote:

Originally Posted by CornedBee
Do you mean momentum?

The principle of moments is derived from Archimedes' discovery of the operating principle of the lever. Archimedes was a Greek mathematician and physicist noted for his work in hydrostatics and mechanics and geometry (287-212 BC).

With a lever, one applies a force, in his day most often human muscle, to an arm, a beam of some sort. Archimedes noted that the amount of force applied to the object, the moment of force, is defined as M = rF, where F is the applied force to the lever, and r is the distance from the applied force to the object.
http://www.absoluteastronomy.com/enc..._(physics).htm