SortStack #2990 — 2034-08-16

By speed · Order from slowest to fastest.

1. A slowly marching sand dune 20161.8 mm/year

   Wind pushes desert dunes forward grain by grain, swallowing roads and even villages over the decades.

2. 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.

3. A racing bobsled 150 km/h

   Bobsled crews sprint to shove the sled at the start, then leap in, as those first seconds decide the race.

4. A bullet train at full speed 330 km/h

   Japan's bullet trains have a near-perfect safety record, with average delays measured in seconds, not minutes.

5. The speed of sound at sea level 1.2K km/h

   Sound travels faster in warm air than cold, so a thunderclap's timing shifts slightly with the weather.

6. A .220 Swift rifle bullet 4.4K km/h

   Among the fastest commercial rifle rounds, it leaves the barrel so quickly the bullet can melt slightly in flight.

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