说明
A car speedometer and a clock can be used to measure velocity as a function of time for (provided it only moves forward) a moving car. 用速度表和时钟可以为一辆运动着的汽车(假定它只是向前行驶)测定其作为时间函数的速度。
A car speedometer and a clock can be used to measure velocity as a function of time for (provided it only moves forward) a moving car. 用速度表和时钟可以为一辆运动着的汽车(假定它只是向前行驶)测定其作为时间函数的速度。