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Flight

If humans could fly, without tools and machines,

how fast do you think we would go? As of 2012, the world record

for fastest short-distance sprint speed is roughly 27 miles per hour.

Running speed depends on how much force is exerted by the runner's legs,

and according to Newton's Second Law of Motion, force is the product of mass times acceleration.

And Newton's Third Law states that for every action,

there is an equal and opposite reaction. So, that means running requires

having a ground to push off from, and the ground pushes back against the runner's foot.

So, flying would actually be more similar to swimming.

Michael Phelps is currently the fastest human in water and the most decorated Olympian of all time.

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