在物理学中,把路程和时间之比叫作速度,速度是表示物体运动快慢的物理量,在数值上等于物体在单位时间内所通过的路程.如果物体在相同时间内通过的路程相等,它的速度是不变的,我们把物体沿着直线且速度不变的运动叫匀速直线运动.常见的物体运动都是变速的,即在相等的时间内通过的路程不相等,为了把复杂问题简化处理,可以用平均速度粗略地表示变速运动的快慢. In physics, the ratio of distance to time is called speed, which is a physical quantity that represents the speed of an object’s movement, which is numerically equal to the distance the object passes in a unit of time.If the object passes through the same path for the same time, it Of the speed is constant, we move objects along a straight line and constant velocity called uniform motion. Common object movements are variable speed, that is, in an equal time through the path is not equal, in order to simplify the complexity of the problem Processing, you can use the average speed of roughly that the speed of variable speed movement.