SortStack #1226 — 2029-10-17

By speed · Order from slowest to fastest.

1. The growth of a cave stalactite 0.1 mm/year

   Most stalactites lengthen by less than a tenth of a millimetre a year, dripping mineral by mineral over millennia.

2. An electric scooter 25 km/h

   Shared e-scooters exploded across cities in just a few years, becoming a common sight on sidewalks worldwide.

3. A Cessna light aircraft 220 km/h

   The Cessna 172 is the most-produced plane in history and the trainer that taught millions of pilots to fly.

4. A record tennis serve 270 km/h

   The fastest serves leave the racket so quickly the returner must react before the ball has even crossed the net.

5. A maglev train at record speed 460 km/h

   Maglev trains float on magnets with no wheels, so the only friction left to overcome is the air itself.

6. A 5.56mm rifle bullet 3.1K km/h

   Small, fast rifle rounds tumble on impact, transferring energy in ways a slower, heavier bullet would not.

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