368 ON PHYSICAL DATA 



P P 



Let us now return to the laws -^ + —^ and 



— |- -j ~ and assign particular values to the 



constants P, &c., &c. 



We have shown that equilibrium exists when 



Po-P 



oc zz 



P.-P3 



Let P2 - P=ToVo & Pi - P3=l ; at a unit of dis- 



P P 

 tance. Then the attractive force becomes ^ + -^ 



P I 1 P — 1 



And the repulsive force becomes — ^^ + -^ 



/. X = wro = the distance at which equilibrium 

 will take place. From the above equations we 

 have P3 := Pi - 1 , and P2 =r toW + P . Hence 

 the condition P > P3 , becomes P > P, - 1 ; and 

 P > P2 , becomes P > toW + P ; which is always 

 the case whatever be the value of P . 



P P P 

 The effective attractive force is -^ + -^ ^ 



L__ _ Z- -I- 1 =2 - \ , which is inde- 



pendent of P & P^ 



P 1 



And the effective repulsive force is -^ +looo^ 



