SortStack #1709 — 2031-02-12

By speed · Order from slowest to fastest.

1. The growth of human hair 175.3 mm/year

   Scalp hair grows roughly 1.25 centimetres a month, so a single strand reaching your shoulders is years old.

2. A scurrying hedgehog 6.4 km/h

   A startled hedgehog rolls into a tight ball, raising up to 6,000 spines that few predators dare to bite.

3. 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.

4. A car cruising the German autobahn 200 km/h

   Parts of Germany's autobahn have no speed limit, where ordinary sedans legally travel faster than racetracks allow elsewhere.

5. A golf ball off the driver 340 km/h

   A driven golf ball can briefly spin thousands of times a minute, which is what makes it climb and hold the air.

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.

← All puzzles · Play today’s SortStack