PickVidsCarl Sagan - Cosmos - Eratosthenes
推荐理由
Here is a wonderful video of Carl Sagan explaining it[0].
说明
这是2009年由carlsagandotcom发布的一部讲解，主题归在World history。它讲的是measuring earth's circumference这一支里的具体问题，而不是把整个领域扫一遍。适合按兴趣直接看、不打算先补课的人。内容上可以概括成：A short clip from Carl Sagan's Cosmos in which he explains how Eratosthenes measured the circumference of the Earth using shadows in two Egyptian cities. It is a clear, visual account of an ancient scientific feat.这些读者给出的理由，核心是：HN commenters link it whenever the question of how the Earth's size was first measured comes up, calling it a wonderful explanation.讲法不绑某一条新闻，过几年仍然可以当材料看。从2022年到2024年，有4位不同的读者在4个不同月份把它推荐出来，其中明确叫别人去看的有1次。适合用一集把一个概念补上的人。抓住它用的那个图像或类比，比背公式重要。如果已经会了基本定义，就把注意力放在它怎么把measuring earth's circumference变成能跟着复述的例子。
视频信息
- 频道
- carlsagandotcom
- 时长
- 6 分 42 秒
- 发布年份
- 2009
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