Hi jerry, the question of the distinction between inertia and gravity is
interesting indeed! We are all familiar (hopefully) with the mind
experiment put forward by Einstein in attempting to find a distinction
between gravity and inertia, namely the case of the accelerating lift (with
no windows). ie: if a person is located within a lift that is constantly
accelerating at 1g, how does that person decide whether they are stationary
within the Earths gravitational field or accelerating at 1g in space.
Einstein could not resolve this question. The EFFECTS of acceleration are
the same as the EFFECTS of gravity, on a given mass. Often when force is
spoken about in aeronautical disciplines it is expressed in how many G's
were "pulled" on this turn or that. Spooky eh?
Bill.