246 



rigidly bolted. The experiment consists in displacing the hammer to a 

 certain angular position to one side the normal position and allowing it 

 to drop and impinge upon the steel sphere, noting the maximum angular 

 displacement of both the steel sphere mi and the hammer after impact. 



Fla.l. 



The following (Kiuations tire ;ipplical)le: 



The Coefficient of Restitution = '^■■ 



s' (1 — cos w) — J Ccos a — cos {i) 



J (cos a — cos ") 



(1). 



Thepercentafcc loHSof K.E. = l=(l-?=) - -— ' (2) The values of :<, {i, ", 



ix\\ — in 2 



and w are measured directly ujton tlu' si'''iduate.l scale KSi. 



TABLE I. 



