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What if everyone on Earth jumped at once?

When you jump, you push on Earth as Earth pushes on you. Now imagine everybody doing it together. The startling part is the difference in mass between the jumpers and the planet, followed by the fact that everyone must land again. A simplified Earth-and-jumpers model can follow both stages without predicting a real earthquake or a lasting orbital nudge.

3–7 min

Questions you could explore

  • What would change during takeoff, and what would happen when the jumpers returned?

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