(2)u=0 mig a=mi+m2+J/r2 mg(m2+J/r2） T=mtmatv mim2g T2=mitmatvrs 结束目录m1g r 2 m1+m2 + J a = + = r 2 m1g (m2 J ) r 2 m1+m2 + J T1 = m1m2g r 2 m1+m2 + J T2 (2) m = 0 结束 目录