560 



the diaphragm (assuming parabolic profile) and the baffle respectively 

 areil/ 



(i.fx) 



d Z (t) _ 2 



° + a> z„ (t) 



dt' 



d% (t) ^ dZ (t) 2p e"*/® 



dt2 



9^ dt 



d\(t) ^ dZ^(t) _ 2p^e-"^/Q 

 _ + - 



dt^ 



©* dt 



m 



(30) 



where 



o 



'^7 



c 

 o o 



=«=l;#(-^)■^^ 



e» = 



m 



r o o 



Equations (29) and (30) are to be solved for Z^ subject to the following 

 initisil conditions 



Zo(0) = Zi(0) = 0, 



Zi(0) = Zi(0) = 0. 



(31) 



One obtains 



Zo(*) = I 



(1 ./9) z° (e,t) +^zS 



(^* ,t)l , 



where 



^ 



©* - 0. 



- Q 



(32) 



and 



(e^^) ^ 2p„ Q [sin ui^ t ^ J^O ^e-^/Q - cos ^ ^t)] ^ 



W, 



7vpFr~F^!^ 



(33) 



The quantity Z° (©,t) may be interpreted as the deflection at time t of 

 a diaphragm moSnted in an infinite rigidly supported baffle when struck 



