gravitational potential [plot],

Integrate[-(G M)/r^2, {r, Infinity, newr}]

(G M)/newr

Integrate[-(G M r)/R^3, {r, R, newr}]

-(G M newr^2)/(2 R^3) + (G M)/(2 R)

In[9]:=

gpotential[r_, R_, G_, M_] := If[r>R, (G M)/r, (G M)/R + (G M)/(2 R) - (G M r^2)/(2 R^3)]

FullSimplify[gpotential[r, R, G, M]]

 {{(G M)/r, r>R}, {-(G M (r^2 - 3 R^2))/(2 R^3), True}}

In[10]:=

rE = 6378140 ;

[Graphics:../HTMLFiles/index_81.gif]

-Graphics -

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