SortStack #2699 — 2033-10-29

By duration · Order from shortest to longest.

  1. 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.

  2. A lightning flash from start to finish 198 ms

    What looks like one bolt is usually several return strokes in a row, heating the air to around 30,000°C — five times hotter than the Sun's surface.

  3. 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.

  4. A qualifying rodeo bull ride 8 sec

    Riders must stay on with one hand for the full count to score at all — touching the bull or themselves with the free hand means instant disqualification.

  5. The Epsom Derby, Britain's most famous horse race 2.5 min

    Workforce's 2010 record run covered the mile and a half at over 56 km/h — and the race has been run every year since 1780, even through both World Wars.

  6. The Holy Roman Empire, from Otto the Great to its dissolution 844 years

    Voltaire quipped it was 'neither holy, nor Roman, nor an empire' — yet it lasted 844 years before Napoleon finished it off in 1806.

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