913 
From the data of Section 12 of this appendix (for the ball crusher gauge 
used under water): 
1.22 x 10* secu for 5/32 in. balls 
& 
i] 
& 
li 
1.82 x 10* sec72 for 3/8 in. bells 
Figures I-2 and I-3 show Y and t,, as functions of ty for 5/52 in. and 
3/8 in. balls. 
It is interesting to note the extent to which the inertia of the system 
is instrumental in maintaining the amplitude of the response as the duration t, 
falls below the step response timee Y¥ is down only 10% when t, is 29% less 
than the step response timee 
6. Linear Decay: F(t) = F(l - ) H(t) F 
eee ee 
Substituting into Eq. (I-5): 0 25k 
al al F 
x= uw + H(t) (I-20) 
(Dy? + wo”) Dy o(D,? + w*) pv,” 
F 1 at 1 
F 
x ==(1 = cos wot) H(t) - => Ot OOO" Gt H(t) 
x MO | (D, + 1o)2im> (Dy = 1) (-2105) DP w® * 
lot -iwt 
= AM ~ cos wt) H(t) - —= rp as ean) 
1's ar Mo 2 
x =: (1 = cos ot) H(t) - = (at - sin wt) H(t) (I-21) 
To determine the maximum deformation: 
teie sin ot, - = + = cos ot, = 0 
1 = cos wt, . 
og = ——_——_4 (1-22) 
ty 
=98= 
