outer force

• 外力

outer force的用法和样例：

例句

1. An external force is one whose source is outside the system.
   外力是来源于系统之外的力。
2. Kinematics is defined as the study of motion without reference to massor force.
   运动性是对不涉及重力和其他外力时汽车运动的研究。