Re: Problem

[Bob Sciamanda <trebor@VELOCITY.NET>]

> Immediately following the treatment of circular motion, I always
> generalized to the statement that the acceleration vector can always be
> resolved into tangential and centripetal components.  (Serway does this)

It is good to point out that there is nothing special about the velocity
vector and its derivative - the acceleration vector- in this regard.  The
time derivative of any vector is another vector which can always be
decomposed into parallel and transverse (to the direction of the original
vector) components.  The parallel component affects only the magnitude of
the original vector - and is in fact equal to the rate of change of that
magnitude.  The perpendicular (or "turning") component leaves the
magnitude of the original vector unaffected and affects only the direction
of the original vector.

Bob Sciamanda
Physics, Edinboro Univ of PA (em)
trebor@velocity.net
http://www.velocity.net/~trebor