56 Mr. J. H. C. Searle on the Effect of 



Again," if T = kinetic energy, 



C l dv\ 2 C l d 2 v I 2 



T = hn \ -A dx + \mic 2 \ —, — 7- dx ; 



J a dt\ Jo dxdt\ 



r \ 2 1 



iv\ 2 d 2 v 

 lt\ + dfdt\ 



= >|^°{/;+ f f } <*£, ^ (47) .... (49). 

 Thus, i^,<^I = cf> 



■■- ™&+^*^^ • ( 5 °) 



X. Evaluation of f ° £# + (|F) 2 } <*£■ 



We have d% 4 d% _ 4/ 



rff4 +^ ag- K Jr 



Jp dp + flTf dp + ^ rff /g rff s 

 [/ p ~ds jds'ds s j V q d% )i$-ds d sy 



Therefore, varying X, 

 A^3f/2,7£_/ A^fp_ d fp d % , d d fp d % _ # d d % 



^yp^-jpdx dp dx dp + d\ d? dp d£ ^x dp 



Hence, 



*${rAW}*-f>i%-i 



3jj,d% ,±if z d 2 f z _df L d L a% 



dX dp + dX d£ dp d£ dX dp 



+^i+^§Hff> 



