力

在物理学中，力是任何能够使物体发生某种变化的影响，无论是关于其运动、方向还是几何构造。换句话说，力可以使具有质量的物体改变其速度（包括从静止状态开始运动），即加速，或使柔性物体变形，或两者兼而有之。力也可以用直观的概念来描述，如推或拉。力既有大小又有方向，使它成为一个矢量。它用国际单位制中的牛顿来测量，并用符号 F 表示。

In physics, a force is any influence that causes an object to undergo a certain change, either concerning its movement, direction, or geometrical construction. In other words, a force can cause an object with mass to change its velocity (which includes to begin moving from a state of rest), i.e., to accelerate, or a flexible object to deform, or both. Force can also be described by intuitive concepts such as a push or a pull. A force has both magnitude and direction, making it a vector quantity. It is measured in the SI unit of newtons and represented by the symbol F.