Re: Conrod force/acceleration

[Audinamx@aol.com]

In a message dated 98-01-26 04:43:10 EST, you write:

<< Come again? Is there not a point in time where acceleration and velocity
 are zero? I certainly think so. When there is no velocity, there is no
 acceleration. Acceleration can be zero while velocity is constant, but if
 velocity = 0, acceleration = 0; acceleration is nothing more than the rate
 of change in velocity. At TDC velocity is zero, and therefore acceleration
 is zero, too. Yet the engine is most definitely running.
  >>
... wrong answer here Sarge ... dig out that old Physics 101 book!  

If zero velocity means there is no acceleration how can anything get moving in
the first place?!  Your statement that acceleration is the rate of change of
velocity is correct, but that's about it.  If you assume that the piston is
moving up and down in a sinusoidal manner, then the acceleration will be the
differential of velocity (e.g. a cosine wave).  The sine and cosine are 90
degrees out of phase, so when velocity is at zero then acceleration is at a
maximum.  Similarly when velocity is at a max acceleration is at a minimum.
ALL BASIC PHYSICS!  It is true that I am ignoring the non-ideal effects in
this analysis, but for the discussions here the first order approximation
should be sufficient.

Where's Sir Isaac Newton when you need him! :)

Steve Buchholz
San Jose, CA (USA)