SortStack #2010 — 2031-12-10

By speed · Order from slowest to fastest.

1. A casual cyclist 12.5 km/h

   The bicycle is one of the most efficient machines ever made, turning muscle into distance better than walking.

2. A gentoo penguin swimming 36 km/h

   Gentoos are the fastest underwater birds, porpoising in and out of the water to breathe without slowing down.

3. A charging black rhinoceros 54 km/h

   A rhino's horn is made of keratin, the same material as your hair and nails, not bone.

4. A Bugatti Chiron at top speed 510 km/h

   The Chiron is electronically limited; unleashed, its tyres would tear themselves apart from the sheer forces.

5. A bullet from an AK-47 2.7K km/h

   The AK-47 is the most widely produced firearm in history, prized for working even when caked in mud and sand.

6. NASA's X-43 scramjet 11.9K km/h

   The X-43 set an air-breathing speed record by burning fuel in a stream of air rushing through it many times faster than sound.

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