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BELL SYSTEM TECHNICAL JOURNAL 



considered outside the scope of this paper, except for the following brief 

 statement: 



Both actions fit the definition of shock stated above and the difference be- 

 tween the two is one of size and not of kind. 



Shocks are transients and are conveniently treated by a branch of mathe- 

 matics which is adapted to the solution of problems of this kind; viz, the 

 Laplace Transforms, and the reader is referred to Gardner and Barnes, 

 "Transients in Linear Systems." The nomenclature used here is identical 

 to that of those authors. 



REStLIENT 



^ MOUNTING ARRAY 



(STIFFNESS, k) 



HAMMER 



Fig. 1 — Schematic layout of shock machine. 



The manuscript consists of two parts: In the first, the energy transfer to 

 the base is considered. We are dealing here with rigid bodies; consequently 

 with very small transient displacements and very large forces. These are 

 usually referred to as impact forces or impulses and four such functions of 

 force and time are discussed. Displacements with associated velocities re- 

 sult from the action of impulses on the base. 



The second part deals with the effect of these displacements on the shock- 

 mounted equipment. Although the mathematical procedure is identical to 

 the first part, here we deal with a function of displacement and time. There 

 is no specific name for such a relationship but a suggestive term is "whip." 

 However, the pulse functions represented are the same as those of the force 

 and time function. 



It is assumed that the displacement-time pulse is independent of the subse- 

 quent motion of the mass. 



In considering any kind of shock problem we have the following funda- 

 mental considerations: 



