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Topic: Science!

https://youtu.be/AnaASTBn_K4

"Always be on the lookout for the presence of wonder." -E. B. White

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Re: Science!

Very cool Mark! Thanks

“Trust your own instinct. Your mistakes might as well be your own, instead of someone else’s.” ~Billy Wilder

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Re: Science!

Thanks very much Mark! This is terrific!

'Less is often more!'

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Re: Science!

There ya go.
Nice find Mark.

Ron

It's ok if you disagree with me.
I can't force you to be right.

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Re: Science!

Yes!! Thank you very much Mark, this is my kind of stuff.  big_smile
I had to grin when April explained about boundary conditions and Eulerian/Lagrangian framework - that’s what I have to deal with in my job.
The interesting part starts about 6.45 min in the video: Not only does the crack happen before the cracker is fully extended - not even the thong/fall is fully extended. April has to aim slightly downwards to place the actual crack in the path of the Schlieren sensor, because when the loop opens near the end of the whip the fall accelerates and the cracker pops way above the point she’s pointing at with the nose of the of the whip.
I wonder if a shorter whip would’ve been better for a more detailed resolution of the last part of the motion?! (lower end velocity)
Anyway, this is a fantastic video!

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Re: Science!

And now I wonder, why they didn’t put the most impressive part, an ultra-slow-mo sequence of the whip motion in the behind the scenes video and not in the main video?!  Starts at 14:45

https://m.youtube.com/watch?v=3HABgm-UUi0

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Re: Science!

Wolfgang, I did notice in that slow-mo that her whip's transition is also very weak.
But I think that fits her speed cracking style that she prefer.

Ron

It's ok if you disagree with me.
I can't force you to be right.

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Re: Science!

Ron you‘re right...looks almost like a stockwhip without keeper wink Very obvious at the start of the slow-mo sequence.

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Re: Science!

Cool video!

I'll give it a try, Dad, but it's going to be really hard...kind of like trying to saw something in half using a banana.