- Can you just like ... Yo-Yo like a basic Yo-Yo - Yeah, like this
- But this is not a basic Yo-Yo
No
That is awesome
Nicely done!
This is Ben Conde, he's got a brand new channel on YouTube
Which is about Yo-Yoing like a crazy person
But, I'm going to figure out how this is possible
How this is possible with a string that's not connected to the Yo-Yo
To get it to do all of these insane things
Wow
Gosh!
How did you learn to do that? That's crazy!
Uh
Just a lot of like lonely saturday nights
So watch this motion here, there, and then you tug up
-Yeah you got it -(Derek Laughs) This is not gonna happen!
You got it, dude!
Pull up- ooooh, that was close!
Tug up! Aww...
-Pull up! There you go! -(Derek cheers)
So, how does this work? When the yo-yo is released it unspools as it falls,
gaining kinetic energy and rotational energy from the gravitational potential
energy it had to start with yo-yos can spin really fast, around six thousand
revolutions per minute.
That's about as fast as most car engines can turn over, and this is important
because it gives the yo-yo gyroscopic stability which means its axis of
rotation is maintained even if there's a breeze or some little disturbances
now since the yo-yo has a lot of angular momentum it continues spinning in the
same direction but when Ben tugs the string
he pulls it from one side of the yo-yo over to the other so now as the yo-yo
continues spinning it binds the string to the spool and starts to roll up the string
If you look closely at this shot you can actually see the exact moment
when the string binds to the spool preventing the yo-yo from unravelling
further and falling off the string.
That's all there is to it, yeah, there's no science behind it at all.
To release the yo-yo Ben throws it out and upwards
without pulling back so it completely unspools and continues spinning at the
same high rate of rotation, but how does he catch it with just a string?
So the way yo-yos actually do roll up is there's friction pads inside the yo-yo
these ones are made out of silicone you see this like little gap that inside
when that string goes inside that creates friction and while it's spinning
it rolls the yo-yo up
So if Ben can lodge the string in the gap of the yo-yo
it catches on the friction pads and the yo-yo starts to roll up the string again
Even without the friction pads when the string wraps around the axle it
creates a significant amount of friction in the same way that ropes wrapped
around bollards hold big ships to their docks, the amount of tension a coiled rope
or string can hold is given by the belt friction equation. This equation shows
that the force the string can exert on the yo-yo increases exponentially with
the angle the string makes around the axle so even a few turns around the
yo-yo allow been to pull it back into his hand
(Derek): What is your favorite yo-yo moment?
My freestyle in 2011 the crowd stood up and it felt good
It brought tears to my eyes but I went back to my hotel room to cry 'cause I was happy
It was a good moment
Hey this episode of veritasium was supported in part by audible.com
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to any book for a one month free trial. In the book i'm listening to at the
moment is a classic of science fiction it's Kurt Vonnegut's slaughterhouse-five
an awesome book about becoming unstuck from time it involves aliens and world
war two and kind of this weird time travel but it's just a phenomenal piece
of writing so if you haven't read it or listened to it and you can check it out
for one month free trial just go to audible.com/veritasium I really
want to thank audible for supporting me and I also want to thank Darren Dyke who
filmed the slow-motion shots in this video
he is phenomenal that's why this video is so cool and also of course Ben Conde
because he spent years of his life perfecting the skills that you saw
demonstrated here if you want to see more of him
you can go check out his channel, link is in the description
so again I want to thank all of these people and I want to thank you for
watching