例题 §20动量原理 例题20-7 CO 1sn(2) myco Fx-mg mao=F·Sm(4) 联立(2)(3)(4)解得: C N 1+3sm (个) mg 8sn p( (乙) J (1+3sn2(0)例 题 20-7 §20 动量原理 例题 y o x C B A FN mg 联立 (2)(3)(4)解得: 0 (2) 0 0 sin 2 l y C = − m y C0 = FN − mg (3) 0 0 2 sin 12 2 1 l ml FN = (4) l g mg FN (1 3sin ) 6 sin 1 3sin 0 2 0 0 0 2 + = + = () ()