[[http://www.youtube.com/watch?v=E7vcQcIaWSQ Along the paper faster than the paper]]
[[http://www.youtube.com/watch?v=k-trDF8Yldc Under the ruler faster than the ruler]]
[[http://www.youtube.com/watch?v=9Yt4zxYuPzI Under the ruler 2: the ground moves]]
[[http://www.youtube.com/watch?v=bbF8jtej8jw Under the ruler 3: tilting the ruler]]

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адрес оригинала: ((/Физика/7Б/20100224))