# First, Let's Synchronize Our Watches

Jump!

Leonard Monroe wonders: "What would happen if everyone in the world were to jump and land at the same time?"

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It would make some noise, and we would all have wasted a few seconds of our life.

we did this problem in physics class with an average weight of 200kg i think(yes we made it large). if all the people are in the same area, the earth moves a ridiculously tiny amount in the opposite direction, then the gravity pulling the people back undoes that movement. so all we would accomplish is a world record...as long as the ground is stable enough at that location, which would be large for the population of the earth.

you missed it!
http://www.worldjumpday.org/

well earth's mass is 6e24 kg, humanity has 6e9 souls @ ~75 kg giving a mass of 4.5e11

you could work out the momentum (p=mv) of earth with its speed orbiting our sun... and assume a jumping height of 10 cm for each human and get a total sum of momentums for the system... you could figure out the distribution of each jolt by continental density and how it was aligned in the rotation at the time of the jump causing more effect if the resultant force is opposing our path through space. you could even factor in the material properties of the underlying rock to absorb or transmit the energy...

but you know what??? earth is 14,000,000,000,000 (14 trillion) times more heavy than humanity... thats like 1 child jumping up and down on Mount Everest and expecting it to crumble.

people are reasonable distributed around the world so if jumping did any thing it would cancel it self out.

Here's my take on this:

If you got every human to jump at the same time it would be a great sign. If you got every single human to do something as simple as jumping up at the same time, you could ask them to do other stuff like helping the guy next to you, or sharing a meal. This by far would have more implications than the simple act of jumping.

So my answer is, you wouldn't phisically move planet Earth but you would surely move the world in a new direction.

How inspiring, but if I could get everyone in the world to do something it would be to send me a dollar.

### June 2013: American Energy Independence

Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.

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