A treatise on the rectilinear motion and rotation of bodies; with a description of original experiments. Relative to the subject / By G. Atwood.

  • George Atwood
Date:
1784
Catalogue details

Licence: Public Domain Mark

Credit: A treatise on the rectilinear motion and rotation of bodies; with a description of original experiments. Relative to the subject / By G. Atwood. Source: Wellcome Collection.

    33/484 page 9
    From thefe confiderations it appears, that in whatever degree the hardnefs of perfedtly elaftic bodies may differ, the effects of their impadts on each other will be the fame, the weights and velocities before the ftroke being given. For the figures of the ftriking and of the other body mull continually change, till they have acquired a common velocity, which depends only on the weights of the bodies and velocity of the impadl, and is determined by the rules for the collifion of nonelaftic bodies. Moreover, the re- ftoration of the changed figures, how fmall or great foever may have been the change, mull caufe an addition of ve- locity in the ball ftruck equal to that received from the impadl. It follows alfo, that the effedls of the ftroke will be the fame, whether both bodies be perfedtly elaftic, or one per- fedtly elaftic, and the other perfedtly hard, every thing elfe being given: for the figure of the elaftic body itiull change till the bodies have obtained a common velocity, which depends on the weights and velocities before the ftroke only, and will be the fame as if the bodies were nonelaftic; the reftoration of the figure will in this, as well as in the former cafe, caufe an increafe of velocity in the ball ftruck equal to that before communicated. Although no fubftance in nature poftefles perfedt elafti- city, or is entirely deftitute of it, yet there are feveral elaftic and nonelaftic bodies fubjedt to experimental trials, wherein the laws relating to collifion, are found to agree with matter of adt, to a confiderable degree of exadlnefs. IX. The accelerating forces which commu- nicate velocities to bodies, are as the moving forces diredtly, and the quantities of matter moved inverfely. Since the accelerating force* is as the velocity gene-* Art VI. rated m a given time, and by the laft article the moving force is as the quantity of matter and velocity generated m a given time, it follows that the moving force is as the accelerating force, and the quantity of matter moved joint- ly ; that is, the accelerating force is as the moving force dtrettly, and the quantity of matter moved inverfely. f o illuftrate this, let^and q denote any two mafles of ma ter . let m be the force or weight by which gravity im- pels q towards the earth’s centre, and let Af be any other fore#
    digitised image 1
    digitised image 2
    digitised image 3