来自《耶鲁大学开放课程：基础物理 第11集 第11集》

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  Now, maybe we can draw it like this.
  或许我们可以这样画
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  It's a disk in this case,
  在这种情况下 是个圆盘
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  which is spinning like that.
  它这样旋转
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  Everybody with me now?
  大家跟上我的思路了吗
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  There is a little tower
  这里有个小塔
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  and on the apex of that you take a massless rod, if you like,
  但顶端处有一根无质量的绳子
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  put a gyro here.
  在这里放一个陀螺
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  And first of all suppose it's not spinning.
  首先假设它没在旋转
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  I am going to--I'm holding it here and I'm going to let it go.
  我要 我在这儿抓着它 然后放手
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  What's going to happen to the gyro is what we're asking.
  我要问的是 陀螺会怎么样
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  The gyro is not spinning.
  陀螺没有在旋转
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  Everybody should know, you don't need physics 200
  每个人都应该知道 会发生什么