SortStack #2790 — 2034-01-28

By duration · Order from shortest to longest.

  1. A single wingbeat of a hovering hummingbird 12.6 ms

    Up to 80 wingbeats per second lets hummingbirds hover, fly backwards, and even fly upside down — no other bird can do all three.

  2. 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.

  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. One full rotation of the London Eye 30 min

    It moves so slowly — about 0.9 km/h — that it usually doesn't stop to let passengers on; you simply step into the moving capsule.

  5. The main construction of Notre-Dame de Paris 97 years

    The medieval build ran from 1163 to 1260 — yet after the 2019 fire, the cathedral was restored and reopened in just five years.

  6. The Hundred Years' War between England and France 116.6 years

    Despite the name, it lasted 116 years (1337-1453), punctuated by long truces — and technically England and France stayed at war on paper even longer.

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