来自《耶鲁大学开放课程：基础物理 第2集 第2集》

• 
  
  You cannot say,
  你就不能再说
• 
  
  "I never heard of it. I don't know where it came from."
  "我从没听说过 我不知道它是怎么来的"
• 
  
  You should think about why that is true.
  你应该想一想为什么那是正确的
• 
  
  If you do that, you will find this result.
  如果你思考了 你就会得到这个结果
• 
  
  So, there is a way to go from the unprimed coordinates
  现在我们有一种方法可以从原坐标系
• 
  
  to the prime coordinate by rotating your axis
  转变到新坐标系 只要旋转坐标轴
• 
  
  and actually calculating the components.
  并实际地计算一下坐标即可
• 
  
  Now, here is a very important message, which is the following.
  接下来将有一个非常重要的信息
• 
  
  When you go from one set of axes to another set of axes,
  当你将一组坐标轴变换到另一组坐标轴时
• 
  
  the numbers change.
  坐标值会发生变化
• 
  
  The components of the vector are not the same.
  矢量的分量和原来的也不再相同
• 
  
  You might think it's all along x
  你可以认为它是沿着 x 轴的