# RE: Conrod force/acceleration

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has this become an issue of semantics or one of defining of terms and not mathematical?

If acceleration is a function of a change in velocity over some sampling
period, then we cannot really talk about acceleration relative to 'instants in time'
(like the instant while the piston is at TDC) , can we?

If there is no definition for acceleration for an instant in time, what is the conceptual model?

-glen

It seems the assumption is that velocity is zero for one instant, not two
instants - eg v never = 0 for two trillionths of a nanosecond. if it did, for
two trillionths of a nanosecond, then acceleration would be zero, as v is zero
for that length of time. What the scientific community would have is that zero
only exists for one trillionth-of-a-nanosecond during the reversal of travel.
I believe that for two trillionths of a nanosecond you might have zero
velocity as the crank swings by to pull the piston back down, owing to
IMPERFECT properties of the sytem upon which you are practicing perfect
theoretical trig.

You are praticing perfect math on an imperfect object. The math, if adhered to
<snip>

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