Then, you've got to say, "What do I have to know about this object at the initial time?
然后,也许你会问,我需要知道物体初始状态的哪些信息呢
Simply knowing the acceleration is not enough to tell you where it was at the initial time.
仅仅知道加速度是,不足以告诉你它在初始时刻的位移的
So the meaning of the constant is where was the object at the initial time.
常数的含义是,物体的初位移
You get to pick where it was at the initial time.
你需要选取初始时刻的位移
By "Present," We mean-- we will pick some part of the universe we want to study and we will ask, "What information do I need to know for that system at the initial time, like, right now, in order to be able to predict the future?"
我们所说的"现在",意思是,我们会选取客观世界某一部分来进行研究,然后我们就会问,我们需要什么信息去了解,初始时刻的系统,比如现在,进而能使我们能够预测未来呢
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
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