Stabilized-platform weighing scale of novel design. . n this way, every slight difference in the manner in whichthe balance is set in motion will result in a different rest the third method, when the balance has static friction, the restpoint will lie invariably on a determined side of the true point ofbalance, depending upon the direction in which the one excursionhas been made; in other words, the excursion, no matter fromwhich direction executed, will be consistently too short, and thefinal reading will be in error either in excess or deficiency, accordingas the reading has been ta
Stabilized-platform weighing scale of novel design. . n this way, every slight difference in the manner in whichthe balance is set in motion will result in a different rest the third method, when the balance has static friction, the restpoint will lie invariably on a determined side of the true point ofbalance, depending upon the direction in which the one excursionhas been made; in other words, the excursion, no matter fromwhich direction executed, will be consistently too short, and thefinal reading will be in error either in excess or deficiency, accordingas the reading has been taken at decreasing or increasing load. We have seen, then, that in no case can a balance which hasstatic friction give correct readings of the rest point. No proofis needed to show that upon the determination of the true restpoint the accuracy of all weighing depends. In the ordinaryplatform scale we adjust by trial the equilibrating forces until theend of the beam plays, as closely as can be judged, in the center Stabilized-Platform Weighing Scale n. Fig. 6.—Curve of damped oscillations, reproduced from photographically recorded oscillogramThis is a vibration of the form, 0= horizontal axis is that of time, while the vertical axis is that of angular displacements from the initial plane of balance. The value ^7 gives a measure of the amount of the damping. The values of the loadcorresponding to each oscillogram are recorded in each case. For example, in the curves of this figure, ais the oscillation for the scale with a load of pounds, the distance x from the vertical plane throughthe load knife-edge being inches. In b, an increment of pound has been added, and in c, an addi-tional pound. At d both increments have been removed together, and at e both have been readded,together. Note the accuracy with which the axes of a and d, and of c and e, are collinear, curves of this figure are taken from a scale having the type of stab
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Keywords: ., bookcentury1900, bookdecade1910, bookpublishernationalbureauofst
