1186 
-2- 
Now the time t at which the plate leaves the water is given by 
a 
eae oe oe SF (57) 
Cc 
Where t', if the solution is valid, is given by equation (52) or (26) according to whether € is 
large or not. Equation (57) gives the relation for the time t at which the separation reaches , 
distance r from the centre of the plate and thus 
velocity of separation = = (58) 
and from (57) 
Ot = i 5 Cha t" ae (59) 
or c rc) A Ry 
(i) € not large. 
Then from equation (26) 
One: (Olt £0.e Kot! 2 os € loge€-€+1 (60) 
R OR, O€ Ry O€ n Ry (e - 1) 
It can easily be shown tnat as € increases from 0 to© the function in brackets In 
equation (60) decreases steadily from 1 to 0. 
Hence 
: 
o> Shp - 4b (61) 
0 Dro 
whence from (59) 
IOS SCRE cts cca en ea (@) 
c Roe or RPalinc n Ry 
provided nR /c 21. As shown in Appendix | this latter is satisified by smal) amplitude 
underwater explosion waves and thus from (62) 
(uel Is 
; c (63) 
(ii) € large. 
From equation (51) regarding a, asa function of Ry we nave 
da, “ Be €@ (su) 
OR, na 1 c/n R Sateen RB)? i 
defining O which is of order unity since n R,/c is of order 6 or greater. 
Hence from equation (52) 
2 
ot’ 1 Log a (Log a.) 0 1 Loa 
— = 2 Selle thse Pe a ae eee (65) 
> nk, € 28ae a, Ba a, 
Since ceoes 
