Leaf Duo

做物理作业，看到这样一句话，说：牛顿第一定律是独立的一条定律，绝不能简单地看成牛顿第二定律的特例。于是，我就不理解了，再于是， Google 之，找到一些，但是不太清楚， 于是 Wikipedia ，在英文版找到了答案： http://en.wikipedia.org/wiki/Newton%27s_laws_of_motion#Newton.27s_first_law:_law_of_inertia
Every body perseveres in its state of being at rest or of moving uniformly straight forward, except insofar as it is compelled to change its state by force impressed.[8]
This law is also called the law of inertia.
This is often paraphrased as "zero net force implies zero acceleration", but this [...]