16 / 18 : Visit of Questacon with my friend Dai Chaoqing and his family, Canberra, 30.03.2014: Questacon20140330 124425
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The strings of the pendulums had different length. |
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The strings of the pendulums had different length. The different oscillation frequencies caused nice waves of the balls.
- 2014 Mar 30 12:44:25
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