supplied to the Primary Coil of a Transformer. 483 

 Let 8 be the reading on the torsion-head ; then 



h C T . 

 S=s h i 2 dt ; k being some constant. 



^rpAiAiJ sin(at— ty^ sin (at— fa) dt, 





(fa - fa) -cos(2at-fa- fa) J. dt, 



JcAiA 



l-^cos^!-^ 



). 



Now A 2 =|, where S=\A 2 2 + a 2 L 2 2 . 



Hence 



k EAj , . 



^•-g-cosC^-Va)- 



Now mean power, or 



1 T T 



1 j T 



i r T 



= ~r EA X 1 sin at . sin (a£— i/rj) dt 



EA, 



— s cos ^i. 



Therefore 

 But 



COSl/r, 



£m- 



T 



""COS^-^) 





COSl/r 



L 



COS^ 





COS (l^! — 



W 



~ cos i/rj cos fa + sin ^ sin fa 

 i 





1 



COS ^ 2 







~ 1 + tan fa tan i/r 2 



_ Vl + tan 2 ^ 

 1 + tan i/^ tan fa 





cos yjr 



V^ 



COS (t/tj — 



^) 



j j a^LiLg 







r,S 



r^s 





n^2+« 2 LiL 2 







_s 



nS 2 





Hence 



h r ± r 2 + a 2 LxL 2 



