22.答案：F0/4m (F0-F)/4mπ^2n^2 在两极 GMm/R^2=F0在赤道 GMm/R^2=F+m4π^2n^2RR=(F0-F)/4mπ^2n^2在h=R时GMm/4R^2=F0/4=mg'g'=F0/4m
