Conducting Sphere on Magnetic Induction. 



fi(2n+l) 



173 



n 'a\ 2n + ] 



n + 



i(ri 



T d = real part of ^j-^+^j -^-J 



e^rjyQn 



(Uln 



ds 



T,=^| 1 +S+IU) i 1 " ~2^a-J j C0S k* + *-> -2T' 



In these formulae (13) and (14), for R^ and T^ it is assumed 

 that H n is wholly real ; this is the case in the application we 

 are going to make. 



Let the magnetic field outside the sphere be due to an 

 alternating current in a circular circuit whose axis passes 

 through the centre of the sphere. 



(14) 



Fig. 1. 



Let be the centre of the sphere, 

 B the centre of the circuit, 

 A any point on the circuit, 

 P any point. 



Let BA=/; 



OP = r; 



ZBOA=a; 



OA = c; 

 ZBOP = 0. 



Let f) be the solid angle subtended by the circuit at P. 

 ye' pi the current in the circuit, 

 V the potential due to the circuit at P, 

 U the magnetic force along OP. 



