Re: Inertia

[brian whatcott <inet@intellisys.net>]

At 20:31 11/27/97 -0800, Leigh wrote:
> While mass is often called the coefficient of inertia, inertia *per
> se* refers specifically to the force a body exerts upon any agency
> which acts to change the body's motion. That phenomenon was referred
> to as *vis inertiae* (the force of inertia) by Newton. Of course
> Newton did not claim to have invented it, since the recognition of
> the phenomenon antedates Newton ...
> Leigh
In reading Definition III of Principia, I get a sense that Newton
could have originated this particular term - he reaches it by means 
of a small discussion:

"The Vis Insita, or innate force of matter, is a power of resisting,
by which every body, as much as in it lies, continues in its present 
state, whether it be of rest, or of moving uniformly forwards in a 
right line.
....
A body, from the inert nature of matter, is not without difficulty 
put out of its state of rest or motion. Upon which account, this 
vis insita may, by a most significant name, be called inertia 
('vis inertiae') or force of inactivity."

Newton, trans Motte/Cajori

Sincerely
brian whatcott <inet@intellisys.net>
Altus OK