Inspired by the urban legend that if all the people in China jumped at once it would alter the orbit of the Earth, German scientists (working in participation with a German TV show) staged an experiment
at a music festival. They arranged for all 50,000 people at the concert to jump at once, and then measured the results. They called it a "gang boing." Here's what happened:
In the end, the hoppers created "a mini-mini-earthquake," according to Ulrich Grünewald, who produced the segment for a science program on German television. The ground moved one-twentieth of a millimeter, with four oscillations per second. Scientists from Germany’s Geological Research Institute measured movement up to a kilometer away...
"We showed that people cannot start a (real) earthquake by hopping," Grünewald told the dpa news service. An actual earthquake would contain billions of times more energy than the jumping Germans produced.
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