(1)m2=2m1 r2=2r1m1v1^2/r1=GMm1/r1^2v1=根号下GM/r1m2v2^2/r2=GMm2/r2v2^2/2r1=GM/(2r1)^2v2=((根号下2)/2)*根号下GM/r1v1:v1=1:((根号下2)/2)(2)w=v/r自己再代入算(3)T=2π/w自己再代入算(4)F向=ma=mw^2r=mv^2/r=GMm/r^2自己算