362 ON PHYSICAL DATA 



-^t;^ W 



p p 



Therefore, when a^ — -^ — p- , we shall have 



■T] — -T 3 

 p p p p . „ . 



-L. 4- _iL = ±1- -I 5_ or the attractive lorce is 



x^ X ar X ' 



equal to the repelling force. 



If we substitute this value of x in either of the 

 expression ^ + ^ , or -^ + ^ , we shall have 



the force to which however little is added, the 

 sum will be sufficient to disturb the equilibrium 

 of the two particles. Making this substitution 

 we shall have 



P , P, _ F(Pi-P3)' , P.(Pi-P3 ) 

 IF "'' ^ ~ (P.-P)' "^ (P2-P) 



_ P(Pi-P3)^ Pl(P.-P3)(P2-P) 



- (P3-P/ "^ (P2-P)' 



( P(P,-P3)+P.(P.-P) Ut> p 



_ (P. P,-PP3)(P,-P3) 



(P^-P/ 



_5p I p (P.-P3) ? (P.-P3) 



- r"'" (P2-p)HP2-p) 



