Counting calories while one dynes invariably takes the edge off one's enjoyment, if not the appetite. Avoiding such activities whenever possible is bound to give one a rounder tone, though measureably more sluggish action. Inertia, being loosely defined as resistance to change, can be a fairly accurate descriptor of piano technicians in general, but especially so after having over-consumed at the Christmas table. The force required to overcome the inertia of the piano tech in a state of rest is inversely proportional to the bank balance of PT in question, multiplied by the leverage applied by the spouse of said individual. Therefore, the MOI may be defined as the point in time when the piano tech is ejected from his/her state of torpidity trying to decide who really are the champions in the pletohora of bowl games, tools in hand, into the cold, harsh reality of the January air. This may be encouraged by a wipp assist from afore-mentioned spouse. The tax man cometh! Otto ----- Original Message ----- From: "Richard Brekne" <Richard.Brekne@grieg.uib.no> To: "College and University Technicians" <caut@ptg.org> Sent: Thursday, January 08, 2004 1:41 AM Subject: Re: Keys and MOI - wipp assist > > > "Don A. Gilmore" wrote: > > > > Hi Ric: > > > > No, I think John is just converting mass to force on earth. You have to > > multiply grams by the acceleration of gravity to get the force they exert > > downward on earth (the "weight"). It doesn't have anything to do with the > > acceleration of the object by outside forces. > > > > W = m * g > > > > where W is weight, m is mass and g is the acceleration of gravity. > > > > It's common for folks to confuse weight with mass. They are really two > > different things. Grams are mass, not force. The units that John shows > > > > g-cm/s^2 > > > > > Thanks Don... I was pretty sure thats what he meant... just needed a > clarification.... I mean you never know ... grin.. Typos are best > cleared up by the authour, not the questioner. > > > > are actually units of force, believe it or not. Usually this would be > > converted to "dynes" > > > > 1 dyne = 1 g-cm/s^2 > > > Ok on the force bit... but the "dyne" is an unfamiliar term...Thanks > muchly for the explaination below, but I am unsure as to whether or not > John consciously used dynes... I mean... why use them in this case ? And > why was an explaination in terms of ergs lacking then. No matter really. > But for fun.. lets see... John cited a BW force of "45gm*980cm/sec^2 - > 10gm*980cm/sec^2"... that would be 35 dynes then eh ? > > > > > > "But hold on, Gilmore, what is this 'dyne' nonsense?" Well, since F = ma, > > force actually has units of mass times acceleration, or > > mass-times-distance-per-time-squared. So that we don't have to write out > > these big units, a hybrid unit was created. John has elected to use cgs > > (centimeter-gram-second) units, which are used mainly in theoretical physics > > and chemistry. The unit of force in this system is the "dyne". The unit of > > energy would be the "erg", which is a dyne-cm. > > > > In all of my posts I use the more common MKS system (meter-kilogram-second), > > which is used in all branches of engineering. The unit of force in the MKS > > system is the "newton" > > > > 1 N = 1 kg-m/s^2 > > > > And energy is in units of a "joule", which is a N-m. There are 100,000 > > dynes in a newton, so they are very, very small. The MKS system is used > > because it relates better to all the other areas of engineering. Volts and > > Amperes, for example, are MKS units (volts can actually be expressed in > > meters, kilograms, seconds and coulombs). > > Ok... this is neat to know really... We could speak in terms of Calories > I suppose if we wanted to... but which would you say is best to use for > our present application... newtons or dynes ?? > > > > > If using the English system, distance is in feet, mass is in slugs and time > > is in seconds. > > > > 1 pound = 1 lb = 1 slug-ft/s^2 > > > > English energy is in ft-lbs (there is no hybrid unit). > > Ahhh.... so thats where the "sluggish" terms thrown around the last > couple days come in. > > > > > Hope this helps! > > > > Don A. Gilmore > > Sure it does... The more we get familiar with physics terms and concepts > as they are meant to be used the better. Some of our throng are more > familiar then I, some less... but most of us benifit from this kind of > post methinks... Thanks muchly Don > > Cheers > RicB > _______________________________________________ > caut list info: https://www.moypiano.com/resources/#archives
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