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GRAVITY AND 

 MAGNETIC 

 EFFECTS OF 

 SUBSURFACE 

 BODIES 



P. A. Rodgers 



ATTRACTION OF 

 MASS PARTICLES 



Newton's law of gravitation states that two 

 particles of mass m^ and m 2 attract one an- 

 other with a force given by 



F = k 



m 1 m 2 



7£ 



(!) 



where, using the c.g.s. system of units, F is the force in dynes and r is the 

 distance separating the particles measured in centimeters. The value used for 

 the constant of gravitation k is 6.670 X 10 ~ 8 dyne cm. 2 /gm. 2 . If r is the vector 

 drawn from mx to m 2 , then the force F acting on mi would be given by 



F, 



km 1 m 2 r 



y3 



and the force F 3 acting on m 2 would be given by 



F 2 = - 



yyS 



(2) 



(3) 



For the purpose of studying the gravitational force field in the neighbor- 

 hood of a mass particle nij, it is convenient to associate with each point in the 



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