来自《耶鲁大学开放课程：新生有机化学 第5集 第5集》

• 
  
  Well you can make a graph that's a wave, that involves light.
  其实你可以将波画出来 包括光
• 
  
  So here what we're going to plot is the force on a charge.
  在这里我们要画出电荷上的力
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  The charge is at a particular position.
  电荷在一个特定的位置
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  We'll have the charge over there on the right;
  我们将它放在右侧
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  it's fixed there, and we're going to measure the force on it
  固定在那 然后测量其上的作用力
• 
  
  that'll make it accelerate up or down. Okay?
  力的作用会使它加速上升或下降
• 
  
  Oops. It doesn't work quite the way it does on mine.
  这和我电脑上的效果不一样
• 
  
  Please let me know when that happens.
  为什么会这样
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  No maybe it's going to work.
  现在好像正常了
• 
  
  What that first thing did was went up and down,
  它首先是上下运动
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  up and down, up and down. Okay?
  上 下 上 下
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  But if you plot it then as a function of time,
  但是当你用时间函数来表示时