a = 2m (286) 



Therefore, we obtain 



Attoj 



The determination of the phase of m(x) needs some consideration. Choose 

 the vertical velocity of the cylinder expressed by 



2g? A 

 V = — == (A n cos 0Jt+B_ sin U)t) (288) 



1T(jOB 



in such a way that the source term has the phase like sin cot. If we write 

 the vertical movement of the cylinder as 



Z = Z A e iWt+i3 (289) 



the vertical velocity becomes 



V = oo Z A ^+13+1^/2 (290) 



A 



Then the phase angle of the source is given by 



where 



6 1 (x) = a + 3 (291) 



tan a = B Q /A (292) 



The amplitude ratio of the radiating wave is, on the other hand, given by 



99 



