> "Don A. Gilmore" wrote: > > Hi Richard: > > You're confusing a lot of terms. Inertia is not a quantifiable > property of anything, it's an effect. It's not an adjective, it's a > noun. You don't add or subtract inertia from anything. It's just a > scientific property. I think what you are thinking of is just mass > and moment of inertia. Mass is the quality of an object that causes > it to resist being accelerated. Moment of inertia is the "rotational" > equivalent of mass and is the quality of a rotating object that causes > it to resist angular acceleration (speeding up or slowing down of > rpm). The moment of inertial is different from mass since it takes > into acount the distribution of matter. In other words, the more > material that is further from the pivot point, the harder it is to > accelerate (or decelerate) the object. That's why flywheels have most > of their mass toward the outer perimeter. > > Ok... had to think on this a bit to put my finger on what bothers me about it. First you say inertia is not a quantifiable property, yet few would dispute that the more mass a thing has.. the greater its inertia. You seem to be doing so. Secondly.. you go on to say that in the case of rotational mass this equivalent tendency to resist changes in velocity is indeed a quantifiable thing... this since we can quantify the moment of inertia and because <<Moment of inertia is the "rotational" equivalent of mass>> This begins to sound more like Sarah and Mark telling us that a things inertia is a things mass. In any case, why is inertia quantifiable only if we are dealing with rotation ? Cheers RicB Unnecessary text and HTML formatting removed :) -- Richard Brekne RPT, N.P.T.F. UiB, Bergen, Norway mailto:rbrekne@broadpark.no http://home.broadpark.no/~rbrekne/ricmain.html http://www.hf.uib.no/grieg/personer/cv_RB.html
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