Re: Apparent Weight

["James W. Wheeler" <jwheeler@eagle.lhup.edu>]

> From B.P. Cowan, "Classical Mechanics" Routledge and Keegan Paul plc 1984

Mach's Formulation of Newton's Laws

1.  (Experimental Proposition) When two bodies interact they induce in
each other oppositely directed accelerations.

2.  (Definition) The mass-ration of any two bodies is the negative inverse
ratio of their mutually induced accelerations.

3.  (Experimental Proposition) The mass ratio of bodies is independent of
their physical state.

4.  (Experimental Proposition) The accelerations which any number of
bodies induce in a body are independent of each other, i.e. forces add as
vectors.

5.  (Definition) Force is defined as the product of the mass of a body and
its acceleration.


Comment-(mine)  Forces are useful because they seem to obey repeatable laws.