作用力等于反作用力，这是牛顿第三定律，因此Fij与Fji完全相等，但它们方向相反。

Actions equals minus reactions, according to Newton's Third Law, so this force, Fij, will be exactly the same as Fji, except in the opposite direction.

youdao

作用力等于反作用力，这是牛顿第三定律，因此Fij与Fji完全相等，但它们方向相反。

Actions equals minus reactions, according to Newton's Third Law, so this force, Fij, will be exactly the same as Fji, except in the opposite direction.

youdao