Kinetic energy is the energy a particle or body possesses because of its motion; it increases with both mass and speed. In a substance, the average kinetic energy of its particles is what its temperature measures. It contrasts with potential energy, which is stored energy associated with position or configuration.

动能是粒子或物体因运动而具有的能量;它随质量和速度的增大而增大。在物质中,其粒子的平均动能正是温度所衡量的量。它与势能相对,势能是与位置或构型相关的储存能量。