One is inertial mass, which is how much you hate your velocity to change, how hard you resist acceleration.

一个是惯性质量,它反映了物体速度改变的难易程度,即保持加速度的难易程度

耶鲁公开课 - 基础物理课程节选

The first one is velocity, the second one is acceleration.

一阶导数叫速度,二阶导数叫加速度

耶鲁公开课 - 基础物理课程节选

Once you can take one derivative, you can take any number of derivatives and the derivative of the velocity is called the acceleration, and we write it as the second derivative of position.

只要你能求一阶导数,你就能求任意阶的导数,速度的导数被称为"加速度",我们把它写成位移的二阶导数

耶鲁公开课 - 基础物理课程节选

Once you've got that, one derivative will give you the velocity, then in a crunch you can eliminate t and put it into this formula.

一旦你得到了这个,求一阶导数就能得到速度,然后你可以消去t,把它代入这个式子

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Then, to find the meaning of b, we take one derivative of this, dx/dt, that's velocity as a function of time, and if you took the derivative of this guy, you will find as at+b. That's the velocity of the object.

接下来,为了弄清b的含义,我们取它的一阶导数,dx/dt,得到速度作为时间的函数,如果你对它求导的话,你会得到at+b,这就是物体的速度

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I think you can tell by analogy with what I did in one dimension that the position of that object at any time t is going to be the initial position plus velocity times t plus one half a t square.

你们可以类比一下我在一维情况下的结论,这个物体在任意时刻 t 的位移,等于初始位移,加上 v ? t + 1/2 ? a ? t^2

耶鲁公开课 - 基础物理课程节选