来自《耶鲁大学开放课程：生物医学工程探索 第18集 第18集》

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  and stress is just force per unit area.
  应力就是单位面积上所受的力的大小
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  You can imagine
  你们可以想象一下
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  if I hang the same weight on this material,
  如果我将同样的砝码挂在这个材料上
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  if it's as material that has a large cross-sectional area,
  如果此材料有较大的横截面
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  it's very thick, or it's a material that's very thin,
  非常粗大或是一个非常纤细的材料
• 
  
  then its deformation is going to be different
  那么它的形变就会不一样了
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  because that force is going to be distributed
  因为力会被分布于
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  over either a big area or a small area.
  非常大或者非常小的一个面上
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  So, the stress is just equal to the force per area,
  因此 应力就等于单位面积的力的大小
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  and we're going to assume that we arranged it in some way
  假设我们可以设定
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  that it's uniform over the area.
  固定的横截面积
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  So the experiment makes sense?
  这个实验能听懂吗