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  • - I think it's time we

  • the scientifically challenged and concentrate

  • on one of science's heroes, Tyler Bradt,

  • kayaker extraordinaire.

  • He wants to kayak over this, Palouse Falls in Washington.

  • Thousands of cubic feet of water pass over this fall

  • every second and drop 186 feet to the pool below.

  • To consider kayaking over this, he must either

  • be a few sandwiches short of a picnic,

  • or a world record breaker.

  • We hope.

  • [music playing]

  • Oh.

  • There he is, the new world record

  • holder of one of the most dangerous stunts

  • I have ever seen.

  • Needless to say, even if you do have a 186-foot water feature,

  • don't try this at home or anywhere else.

  • Falling off a waterfall is the easy part.

  • But as gravity initially accelerates you down

  • at 32 feet per second per second,

  • it's surviving that's the tricky bit.

  • Our kayaker must go over the falls at the correct speed

  • to give gravity just enough time to generate

  • the angular velocity needed to rotate the kayak 90 degrees.

  • This angle minimizes hydrodynamic drag,

  • so he experiences less impact force

  • and cuts through the water.

  • It's also worth noting that a kayak's stability is

  • dependent on keeping the center of mass

  • in line with the center of buoyancy,

  • which is in the middle of a submerged volume.

  • Otherwise.

  • OK.

  • Science-taught, let's see if our team of want-to-be record

  • breakers have learned.

  • He's practicing the science with a man-made kind of waterfall,

  • but the law of gravity is the same.

  • The thin layer of water acting as a lubricant

  • combined with the steep angle allows gravity to do its thing.

  • It's not quite the 32 feet per second

  • per second of a waterfall freefall,

  • but he's only practicing.

  • On to angular velocity, or in this case, the lack of it.

  • Launching too fast meant he gained very little angular

  • velocity, hitting H2O at a terrible angle,

  • thereby maximizing hydrodynamic drag.

  • Which is bad, as it brought him to an almost immediate and very

  • painful stop.

  • Waterfall.

  • Check.

  • Angular velocity.

  • Check.

  • Stability.

  • Check, ish.

  • It's an upside down check, but technically he still got

  • himself into a stable position.

  • It's just a shame his center of mass

  • is directly below his center of buoyancy,

  • as his head is the thing he uses to breathe.

  • Cheering without acknowledging the person

  • that just saved your life.

  • Check.

  • Even if our want-to-be record breakers do get to grips

  • with angular velocity, hydrodynamic drag,

  • and stability, like Tyler did, 186 feet is just too dangerous.

  • Maybe it's better to kayak somewhere safer, like a puddle.

- I think it's time we

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B2 angular waterfall velocity kayak gravity stability

Kayaking Over a Waterfall | Science of Stupid: Ridiculous Fails

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    林宜悉 posted on 2020/10/23
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