- Three, two, one.
Oh, wow, that was loud!
- That was way louder than I thought.
- Hey, it's me, Destin. Welcome back to Smarter Every Day.
Today's question is fascinating.
How hard can you hit a golf ball?
That seems like a really simple question,
but it's very complex.
For example, think about this.
When a golf club is swung and it comes in contact
with a ball at some relative velocity,
there's an elastic collision that takes place.
The ball squishes and then it uses that stored energy
to rebound off the club.
Well here's one way to rephrase the question.
At what point does that ball no longer return
to its original shape?
It goes from an elastic deformation
to a plastic deformation.
I'm not good at golf, but I thought a really fun place
to start investigating this problem
is to use the Phantom camera,
and see how hard I can squish the ball.
Oh, yeah!
So for me this is pretty decent contact,
but obviously it's not hard enough.
So, it's time to move on to the Happy Gilmore technique.
I just hit the ball behind me,
how does that even work?
Number one, I can't swing this club fast enough
no matter how much I Happy Gilmore,
and number two, I can't get good
consistent contact with the ball.
To try to solve this,
I'm working with my buddy, Mark Rober.
He's a YouTuber and an engineer
and we've teamed up with Wix
to actually build two separate devices
to try to solve our problem.
If you don't know who Mark Rober is,
I'm gonna need you to fix that right now.
He's an awesome engineer who's good at designing
intricate devices that answer complex questions
in an awesome way.
Mark's the kinda guy that has stuff he designed
roving around on Mars, doing science right now.
The first video I watched of Mark's
was a roadkill experiment to see if people
were more likely to run over rubber turtles
or rubber snakes.
You probably know Mark from his more recent work.
He's the guy that engineered the glitter bomb solution
to fight off porch pirates.
I'm bad at golf, and you're good at golf.
- And I'm bad at rockets, and you're good at rockets.
- I don't know, you did the Mars Rover.
- There's no rockets on my hardware.
- What are you talking about?
It was like the rocket. - On my hardware!
- Oh on your hardware!
Yeah, yeah, okay, cool. - Yeah, yeah, yeah.
I outsourced that.
- We gonna do this?
- Let's go do some engineering.
- All right, let's do this.
Anyway, you should totally subscribe to his channel
because Mark does stuff like this.
A rocket-powered golf club. - Three, two, one, roll!
(rocket rumbles)
(rocket wooshes)
- [Mark] Yes!
- Where did it go? What happened?
- Go, baby!
- [Trent] That thing is past those trees.
- [Destin] No way.
- Yeah!
- [Trent] It took off.
- That's a cool shot right there, dude.
(rocket whooshes)
- Dude, this is respectable.
(laughs) This is legit.
- Three, two, one, go.
(rocket whooshes)
(laughter)
- Yeah, baby, yeah, go!
That rush you get from an engineering achievement
actually working is like, ah!
Look at the flames.
(rocket whooshes)
- [Destin] It was an absolutely amazing project.
So obviously,
go watch the whole video over on Mark's channel
but even though we could swing the club
way faster than the pro's can,
we still didn't come close
to the mechanical limits of the golf ball.
Instead of hitting the ball with a club,
we're going to hit the club with the ball.
Remember David from the vortex collision video?
This time I've asked David to build a vacuum cannon
that can shoot a golf ball hundreds of miles an hour
without using explosives.
Here's how the thing works.
The barrel is just barely big enough
for the golf ball to slide inside,
so we push it all the way to the back of the tube
and we seal up both ends.
If you pull a vacuum on the inside of the tube,
nature abhors a vacuum,
so if you quickly vent one side to atmosphere,
all the air will rush into the pipe
and it'll push the golf ball down the tube.
This creates stupid fast velocities.
We're talkin' hundreds of miles an hour.
To make it fire even faster than that,
we've put a positive pressure tank on the back side
and we pressurize it with air
so we can fire the golf ball at over 500 miles an hour.
All right, Mark's about to see the device.
See, pressurize that
and then we have the vacuum in the cylinder itself.
And then we have the burst disc in between
and then once the hot wire melts the film,
then the pressurized air will run in there
and there's no air in here,
so there's no drag.
- Yeah, that's the big deal here, right?
'Cause if this was just at 14 psi,
you just have a potato gun, right?
- [Destin] Right, exactly.
- But it's the fact that there's no drag,
'cause that's like what, proportional to velocity squared?
- [Destin] It is, yes.
- That's where you get your massive speed increase,
right? - Exactly.
So to start off,
we wanted to take the stiffness of the club out
of the equation by using something that's pretty much rigid.
- [Mark] This looks like a cartoon.
(laughs)
It's funny 'cause piece-by-piece
this is all coming together.
Like at first I just saw the cannon, then I saw the anvil,
and I'm thinkin' where are we gonna stand?
And then I look over here, (laughs)
and I see this amazing blast wall.
- [Destin] If we get a vapor cloud
that comes out here, this will strip that away
and hopefully, the ball will get straight through,
and then will hit right here in the center of the anvil
and record that with the Phantom
at, what are we at, at 100,000 frames per second.
All right so 100 psi here ready for the vacuum.
(rumbling)
- Three, two, one.
Oh!
I heard it.
- [Destin] Whoa!
- The amount of compression there,
I've never seen anything like that.
Are you kidding me?
- [Destin] I think the back of the golf ball,
I bet that's the weak part.
We then decided to cut a slit in the ball
and see if the outer shell of the ball
was what was holding everything together.
- Okay, three, two, one.
The ball is hot.
- [Destin] Is it really?
(laughs)
It's very hot.
- Yeah.
- Look at it, it like...
- It's like a little mouth and it's like blah.
(laughs)
- [Destin] After that we decided to cut deep enough
to damage the inner structure of the ball
and then see what could happen.
- [Mark] Three, two, one.
(pop)
- [Destin] Whoa!
- [Trent] It's movin' the table.
- [Destin] So all these interesting interactions
that we're seeing play out on the golf ball,
that's a result of an area of physics
called material science.
What we wanna do is we want to explore that a little bit
by havin' a little conversation
about this paperclip.
Let me get this in the vice here.
Okay, cool.
So you know that if you were to push on a paperclip
a certain amount, create a force,
it's going to bend back to where it's supposed to be.
Right?
That's called elastic deformation.
What's happening is the paperclip
is storing the energy that you're putting into it
and then it's goin' right back to where it's supposed to be.
But you also know that if you bend it a little too far,
it's going to move and stay permanently deformed.
That's called plastic deformation.
Different materials have different
elastic and plastic curves.
For example, Play-Doh plastically deforms almost immediately
when force is applied.
Here you can see the difference
between the foam practice ball and a normal.
You can see that the practice ball
is designed to absorb as much energy as possible
so you can practice your swing
without the balls leaving your yard
or knockin' out a window.
I decided to shoot both of these balls against glass
at a much lower velocity to not break it,
just to see what happens at the exact spot
where it impacts.
If you play them in sync,
you can see just how much faster
the golf ball rebounds off the glass.
This is the magic of golf ball design.
You wanna absorb as much energy
as possible during the collision
without getting to the plastic zone
and then you wanna release that energy
by efficiently and rapidly bouncing away.
From goofin' around with this stuff,
we've learned that golf ball impacts
will result in an elastic collision
up to about 300 miles per hour,
which is why it was able to handle the rocket club
without any problems, that was under 300 miles per hour.
But once you get up around 400 or 500 miles an hour,
plastic deformation occurs inside the golf ball.
By the way, that x at the end of the graph,
that's the awesome spot,
that's where we're trying to get to.
- [Mark] That's crazy, dang.
- The vacuum cannon can't quite get these modern golf balls
up to the failure point, so...
- You do that with an old ball?
- [David] Maybe it'll splatter?
- You think?
I don't think an old ball can withstand that.
So where did this come from? - My grandpa's house
- It say 1962 - 1987, wear dated 25 years.
I have no idea what that means,
but mechanically it should be very different.
Oh, yeah. - Oh!
[Mark] There's rubber bands everywhere.
This is gonna be fantastic, high-speed.
- [Destin] We now understand how golf balls work
but we don't understand the mechanical limits of a driver.
There's only one way to figure this out
and that is to shoot a golf ball
at 500 miles an hour against a driver.
- [Mark] Three, two, one.
Oh!
- [Mark] I mean, that was not what I expected.
Dang, dude.
Look at that.
- Three, two, one.
- Yes!
- [Destin] Jeez, man.
- [Mark] Oh, look at the club face. (laughs)
- Okay, so we're gonna do another shot
but Mark had an idea to put an anvil behind...
Genius - Genius idea.
- The golf club here,
but immediately behind it we have the anvil
and the idea is that instead of this thing moving back
because it's transferring momentum into the club,
we're just gonna make mechanical deformation
the only way to absorb the energy.
- How amazing would it be if it bends it way back here?
But it feels like it's maybe more likely
it's gonna come and bounce back out.
But, dude, what a freakin' trophy that would be.
Ball in the middle of that club.
- [Destin] That would be awesome.
- Oh! (laughs)
- Okay, it's Mark Rober,
he can't make a video without using watermelon.
- Destroying a watermelon.
- [Destin] That's his thing.
We get a golf ball goin' stupid miles an hour
but we do agree it's gonna go through the watermelon.
- We definitely agree that.
Okay, the question is does it go through
the tarp on the back side? - And I say, no.
Farewell little guy.
- [Destin] Three, two, one.
Oh!
- There is no chunk larger than like two inches.
- [Destin] Oh, my goodness.
(laughs)
- There's watermelon where?
- [Destin] So it came out of the cannon,
through a watermelon, through a tarp,
through a moving blanket, hit that,
and then somehow bounced over here in this bag.
There's watermelon on the ceilin' outside.
(laughs)
- An elastic collision.
All right I hope you enjoyed this collaboration
between Mark and I.
We asked Wix if they would sponsor
this video collab for us and they were like, yeah.
- Without even knowing very much (laughs)
the brief was like two sentences, so props to them.
- We were like rockets and golf
and I don't even think the vacuum cannon
was a part of the discussion
at one point. - Yeah, we didn't.
- Yeah, so we had to step it up to make this happen,
so big thanks to Wix.
Wix is a really good way to make a website
do anything you want.
- [Mark] I have one for all the builds on my channel
and including my workbench.
It's really clean.
- [Destin] Yeah, that's the thing. It's very clean.
You can grab one of tons of templates
and quickly make a really nice website,
even if you're not that great at graphic design.
I have created a website.
- [Mark] Have you?
- [Destin] Yeah. - [Mark] I haven't seen this.
- It's basically an omage to Mark Rober
and all the reasons you should subscribe
because he's been approaching the subscriber numbers
for Smarter Every Day for a long time now,
but I wanna be the reason that you finally pass me.
- Oh, I see how it is.
So you take credit? - You see what's going on?
'Cause it's gonna happen anyway.
- [Mark] Yeah, yeah, yeah.
So you'll be like... - Exactly.
What do you think is on the website?
For reasons people should subscribe to you?
- Just pictures of my abs.
(laughter)
- [Destin] Pretty much.
So wix.com/go/smarter, no joke though,
I did ThinkerCon's website on wix.com.
Did you know that?
- I did not.
- [Destin] The fact that we made
such a clean, awesome-looking website on Wix
got people really interested in ThinkerCon
'cause it's legit.
I mean, you can tell when you look at the website.
- [Mark] It was a great looking website.
I think I even texted you about it,
like the aesthetic of it is really nice.
- [Destin] That was Wix.
So if you have a personal brand that you want
to get you name out there
and get somethin' out there on the web,
Wix is a great way to do that.
Go to wix.com/go/smarter
and you can start your website today.
Big thanks to Mark for comin' out.
This was a blast.
So go check out his channel, Mark Rober,
all kinds of builds, engineering stuff,
a lot more watermelon carnage than Smarter Every Day.
- This is true. - So go check that out.
Mark Rober on YouTube?
That's how you do that?
- Yeah.
- I'll leave a link in the description.
You can check out my website
on reasons you subscribe to Mark,
but I think you know why you should subscribe to Mark.
It's a big deal.
Anyway, I'm Destin.
- You're gettin' smarter every month.
Oh, wait is it day? - Day.
(laughter)
Idiot. - Sorry.
(laughter)