SortStack #1390 — 2030-03-30
By duration · Order from shortest to longest.
- One full revolution of a helicopter's main rotor 150 ms
Main rotors spin at only a few hundred rpm, but the blade tips travel so fast they approach the speed of sound — the source of that thudding chop.
- An amber traffic light before it turns red 4 sec
Amber phases are tuned to road speed — typically 3 seconds in town and up to 6 on fast roads, calculated from braking distance physics.
- A single round of professional boxing 3 min
Round length was standardized by the 1867 Queensberry Rules, which also introduced gloves — before that, bare-knuckle rounds ended only with a knockdown.
- The construction of the Empire State Building 1.1 years
Crews added roughly four and a half storeys per week, finishing ahead of schedule and under budget during the Great Depression.
- The first circumnavigation of the globe (Magellan's expedition) 3 years
Magellan himself never made it — he was killed in the Philippines. Just 18 of the original ~270 crew limped home aboard one remaining ship.
- The time since the last woolly mammoths died out 4K years
A dwarf population survived on Wrangel Island until about 2000 BC — meaning mammoths were alive while the Giza pyramids were already centuries old.