(bright electronic music) - [Mr.

C] What time is it?

- [All] It's "Science Time"!

♪ Yo, it's science, science, science time ♪ ♪ Let's all stop and just unwind ♪ ♪ One, two, three, four ♪ ♪ Here we go ♪ ♪ Learn so much your brain explodes ♪ ♪ Lessons so cool, so fresh ♪ ♪ Feats so big, you'll lose your breath ♪ ♪ Learning facts and real cool stuff ♪ ♪ Scream for more, can't get enough ♪ ♪ It's, it's science time ♪ ♪ It's fun, you'd best believe ♪ ♪ Explore and learn new things ♪ ♪ Come and join me please ♪ - I'm Mr.

C, and this super smart group is my science crew.

Working together with my crew makes learning so much fun!

Actually, you should join us.

Let's give science a try with a simple DIY.

Today, we're building bridges.

What time is it?

- [All] It's "Science Time"!

- Welcome back to "DIY Science Time".

My name is Mr.

C, and I'm so glad that you're here to be part of our science crew today.

(whip cracks) Today, you and I are gonna connect in a special way.

We are going to build bridges.

These amazing structures are all over the place.

Sometimes they're big, (heavy thud) sometimes they're small, (toy squeaks) sometimes they're short, (xylophone scrapes) sometimes they're tall.

(spring boings) Most importantly, if you grab the following items, you'll be able to build a bridge yourself.

- Let's start connecting the distance between us and build a bridge.

(upbeat synth music) Today, we're building an arch bridge, and trust me, you're gonna need the following materials to make it happen: Sandpaper, mini toy car, (items bleeping) cardboard, sugar cubes, empty tape roll, modeling clay.

And don't forget, you'll need your span-tastic DIY Science notebook.

- A science notebook is a tool that every scientist should have because it gives us a place to record all of our learning.

Taking notes and being organized allows us to be better scientists.

A science notebook allows us to go back and review all of the data and information we've gathered during our experiments.

Plus, it allows us to share results with other scientists who might be interested in learning more about what we've discovered.

Whenever you see the notebook pop up on a screen, like this, (notebook jingles) it's a reminder that this is a good place for us to jot down new information during the show.

I've already added a title and a list of materials for today's activity, but our crew is still going to have lots of information to collect and organize as we go through our experiments.

Most importantly, the more you use a science notebook, the better you'll get at taking notes and recording data.

If you don't have a science notebook already, download a copy of Mr.

C's science notebook from the website.

- Engineers use principles of compression and tension combined with strong materials like steel or concrete to build safe bridges for us to use every day.

(upbeat synth music) Most bridges consist of a flat deck to move the load.

For example, (beams clacking) beam bridges have horizontal beams resting on supports at each end.

Arch bridges are easily identifiable by the arch often found underneath the deck, and a truss bridge uses an assembly of smaller elements to create a rigid and lightweight bridge.

Other bridges use towers to support the deck.

For example, a suspension bridge connects vertical cables from the deck to the large main cables which run over the towers.

Cable-stayed bridges use diagonal cables connected to the towers to disperse the forces acting on the bridge.

So the next time you're on a scenic adventure and see a bridge, look at its shape and try to determine what type of bridge you might be looking at or even moving over.

For our first activity, we're talking bridges, structures, and purpose.

What is a bridge?

Well, a bridge is a simple contraption, maybe not so simple, but it is a contraption and a device that's used to cross between two points.

We need something so that this car can travel from point A to point B. We call that a bridge.

It gets us from one side to the other.

Now, bridges are made of steel, or bridges are made of wood, bridges are made of brick and stone, but today we're gonna be talking about the structure of a bridge.

(voice slows) The structure of a bridge.

And we're gonna see how those structures impact this car's ability to cross this little ravine.

So the first thing is, we need a road to get from point A to point B, and I have this sheet of paper, little piece of paper.

I'm just going to put it just like this.

And as you can see, it's technically a bridge.

(notebook jingles) It gets us from one side to the other, but the thing is, can it hold my truck?

(truck clacks) (buzzer buzzes) (chuckles) No.

So there's not enough support in this bridge to be able to hold the truck.

Now I can take the same sheet of paper and I can fold it in half.

(truck clacks) (buzzer buzzes) No go.

Or I could even fold it like a hamburger bun.

(light upbeat music) (truck clacks) Still not enough strength.

So we need a structure to help support the deck, the bridge component where the car drives over.

And that is why I have these little things called pillars.

Let's put one down for a moment and let's take our road and put it back on and let's see if our car can go across.

Sort of kind of.

The whole cliff fell apart, but it actually had a little more support so I could put another pillar in and put it just like that.

And let's see now if it works.

(wheels whirring) (triumphant fanfare) My bridge worked, but it's kind of weird-looking, right?

You see the bridge here that's essentially just the wall that we've created.

So if we were to remove part of that wall, like in the center, we would create something called an arch.

Look at that.

So now we have an arch that we're going to slide underneath there, and this is another bridge you've probably seen before.

Put that on top, but my arch is just a little... There we go.

And do you think it's gonna hold?

Let's find out in three, two, one... (truck clacks) (buzzer buzzes) No.

(crowd groans) Arch bridges are very strong, but with our paper, it just doesn't do the trick.

So that structure isn't going to work very well.

But there is a bridge that I want you to think about.

It's a truss bridge.

Truss bridges use triangles.

They're the strongest shape.

So what we're going to do is we're going to take a sheet of paper and we're going to triangulate it in a very easy and fun way.

Now we're gonna bring this over here.

We're gonna move our arch out of the way and we're just gonna set this back up.

And now we're going to see if this can hold our car.

And it can.

The triangles help the structure of the bridge and the structure is key to making the bridge work, but this road is not going to allow any sort of car to drive across it because it's wonky.

So we can take this idea of a triangle and build it into the sides or the wall of our bridge.

And what we're going to do is we're going to take another sheet of paper and then we're going to strengthen the bridge by folding the edges over.

Basically, we're going to create a triangle that provides support to the paper.

It's gonna provide structural support.

There we go, we're gonna bring it over here and we have our bridge, and the question is, will it hold our car?

(claps) Yes, it does.

Isn't that awesome?

The triangles are super strong.

(voice slows) So I have a question for you.

Could you build a bridge that uses beams, (notebook jingles) trusses, or arches to hold up a vehicle of your choice?

Not a real car, but like a toy car or a certain amount of weight like with pennies?

I think you could do it.

You can use a combination of things to create your bridge, but you can also have fun exploring what works and what doesn't work.

Remember, the bridge is made of a material, but the structure of that material is going to help the bridge sustain the mass and the weight that has to go over the bridge.

(bell pings) (wheels whirring) (crowd roaring) Yes.

- The Brooklyn Bridge isn't just a bridge.

It's a giant piece of history that stretches across the East River in New York.

(notebook jingles) The Brooklyn Bridge opened in 1883 and was the longest suspension bridge in the world at the time.

Its towers are made of limestone, granite, and cement, and the bridge uses thousands of steel wires twisted into massive cables strong enough to hold thousands of cars every day.

In fact, the bridge allows over 100,000 vehicles to safely cross each day.

From horse drawn carriages to modern day traffic, this bridge has seen it all.

Over 140 years later, it's still standing strong.

(upbeat music) - A career involving bridge building falls under civil engineering (notebook jingles) and structural engineering.

There are different types of jobs which include: bridge engineers who design bridges, bridge inspectors who ensure safety and compliance, and bridge construction workers who perform the physical construction and maintenance of these amazing and important structures.

- This next bridge is going to be sweet.

That's because we're using sugar cubes to build it.

The arch bridge is unique because it has that definitive arch look going on and that helps the structure of the bridge.

Now, in order for us to build that, we need two abutments.

Abutments are basically these blocks of cement or structural support that sit in the wall, and we're going to build abutments using our clay.

We need one on each side of our arch so that the weight and anything that goes on the bridge can be distributed into the abutment.

(upbeat synth music) And then I'm going to form it to have this sort of shape to it.

And that shape is going to allow us to connect it and have our sugar cubes connect to the side.

Now, as you can see, we have our abutments that are gonna sit here on the side, and then we're gonna put our sugar cubes over the top to build our arch bridge.

Now, if I take the sugar cubes and I just place them over the top like this, you can see here that it takes about six cubes, and then when I pull the arch underneath here that's currently supporting it, oh-ho, it did not work.

And that's because the cubes weren't connected and sort of interlocked with one another.

They weren't able to provide any sort of structure and they just fell down.

But we're gonna change that.

We're gonna take this cube and turn it into a trapezoid.

That's right.

We're going to use the sandpaper and sand away the edges (sandpaper scratching) so that we can create an arch that's going to hopefully be able to distribute the weight and we'll be able to put a car on top of it.

You bring it down here to your sandpaper, grind away part of it, (sandpaper scratching) so it has the trapezoid shape.

We're going to build one of these and we have to do this multiple times and then we're just gonna set it down there and then we're going to have to shave multiple cubes down and then we're going to connect it all the way through.

So let's get to it.

(sandpaper scratching) (info panel bleeps) So this is actually a very challenging activity, getting it to fit right going through, but if you take your time and you work the sugar cube, it's gonna work.

And you're trying to get it so that all the pieces are fit really tight to one another.

And then when you get to the last one in the center, this is called your keystone.

Now I have one more little piece, a teeny tiny little sliver, and I'm thinking that this is gonna secure my arch so that it works.

So I'm gonna grind this down and we're gonna test it.

(sandpaper scratching) So I've got my last teeny, tiny trapezoid.

This is the keystone.

Feels a little loose on this side.

We're gonna try to pull this out and see if it holds.

Give it a little bit of assistance so it doesn't slide away.

Oh, this is nerve wracking.

(crowd cheering) Let's go.

That's so cool.

It's so rewarding.

(laughs) I've been working on this a lot longer than you realize, just grinding down.

But look at that, that's an arch.

So the thing is, this right here is super cool because that keystone, that's the last piece that pushes all of the pieces together.

And what happens here, the weight is distributed.

So the weight, say, of a car that sits on top of this pushes downward and then it's all distributed horizontally into the abutments, and that's what makes the arch bridge successful.

So I'm gonna challenge you, build a bridge, have some fun and see if your arch bridge can support any sort of weight.

Should we put our car on this and see if it works?

(crowd cheering) (light upbeat music) It works.

It works.

Build one... (toy squeaks) It still works.

My arch bridge did not fall apart.

The truck fell down, but the arch still stands.

The power of bridges and engineering.

Give it a try.

- Let's get rolling on this next experiment.

Grab some paper and create your own paper tubes.

You can use an old paper towel roll as a template to help make the tubes consistent.

For our first strength test, lay down four tubes and start stacking books on top.

As you can see, the paper rolls hold very little weight, but what if we engineered the same paper in a different way?

This time, fold the paper in half and then roll the paper into a tube and use a small piece of tape to keep it from unrolling.

Place the tubes vertically on the table.

Now begin stacking the books onto the tubes.

Wowsers, look at that.

The tubes are now acting like pillars and can sustain a much greater amount of weight.

Give this experiment a try and test to see if different diameter tubes can hold different amounts of weight.

- Now we're gonna make bridges out of pasta noodles.

That's right, these are bucatini noodles and you can use regular pasta noodles.

You can use whatever you have available at your house.

We're going to build a truss bridge and it's going to be pretty awesome.

Trust me.

(Mr.

C laughs) All right, so here's what I've done.

I've actually gone and I built, well, I've designed what I'm going to make my sidewalls from.

So this is a truss bridge and it doesn't have vertical supports between my triangles.

It's gonna be pretty basic.

So we're gonna build two of these and then I also have a drawing for the base, the deck of the bridge.

We're building a through truss, which means the truss goes above the deck and the car will go through the truss as it crosses the bridge.

So let's get started and we're gonna use noodles and some tape and we're gonna keep it really simple.

You can use different variations.

You can use hot glue, whatever you have available at your house to make the truss bridge, that's what you're gonna make it with.

(upbeat music) (info panel bleeps) We're going to use both tape and glue because the pasta dust is preventing the tape from sticking.

Let's cover the glue with tape for added strength.

We have our first one finished.

Let's build the second one, and because we have a template, they should match nicely so our walls will be identical.

And now we build the deck for the bridge.

This one's a little easier.

It's just straight across.

We're gonna ding, ding, ding, ding, ding, ding, ding, glue everything and we should be good to go.

Each of the noodles is about 10 inches long, so I just made a little template here so I can just come here and crack it.

Oop.

And hopefully that'll give me roughly a piece that'll fit every single time.

All right, so we have the deck built and we have our two sides built.

That looks awesome.

I'm just gonna glue this to this side right here and the tape underneath is catching all the extra glue, so that's good.

Oh yeah.

Oh, that's exciting.

The first wall is up.

I'm just gonna run a bead across the whole thing this time.

I'm gonna make some cross beams up here.

(upbeat music) That's already really strong.

I can feel how sturdy it is because everything is starting to dry.

(screen wipe whooshing) Put the road on the deck and now see if it... (truck whirring) And it works, the pasta bridge.

We though it was im-pasta-ble, but it definitely works.

Super cool, but I want to try to break it.

So this little tub of pennies is two and a half pounds.

Oh, that's like nothing.

It doesn't even phase it at all.

(pennies clacking) All right, that's not gonna be enough.

That's 12 and a half pounds.

I'm not sure if I can... I heard something.

I thought it was cracking.

I mean, what if I just put this on top?

So we have 15 pound- (bridge cracking) I think we should just keep trying this.

Maybe if I turn it sideways like this.

(bridge cracking) (crowd gasps) It wants to go.

It wants to go.

(crowd gasp and murmur) - Oh my goodness.

- I think it's 'cause it's sliding.

Okay.

Oh, I have more pennies over here.

Oh, that's gonna break it.

There's gonna be pennies everywhere.

(laughs) There's gonna be pennies everywhere.

This is another three pounds.

(bridge cracking loudly) (pennies clattering) (crowd cheering) (triumphant organ music) Pasta.

(upbeat music) - The Golden Gate Bridge is a massive suspension bridge that spans the Golden Gate Strait and was built in 1937.

It is an impressive 4,200 feet long.

Each cable is made up of over 27,000 wires, wound tightly together.

If all of these wires were one continuous length, they would wrap around the Earth over three times.

The orange color that identifies this bridge wasn't originally planned.

It was actually a primer that was used during construction, and once people saw the color, they fell in love with it and wanted to keep it that way.

I can see why people really got wrapped up in that bold color.

It's beautiful.

(upbeat electronic music) (stamp thuds) - I'm here at the McWane Science Center with my science crew, and today we're doing an engineering design challenge.

Are you guys ready to have some fun?

- [Crew] Yeah.

- All right.

You will be building bridges that have to be able to hold pennies.

Now, this is going to be the road that sits on your bridge.

We're gonna separate these tables, so your bridge has to be at least nine and a half inches wide or long, and it has to be four and a quarter inches wide.

The rule is going to be the car has to be able to sit on the bridge and essentially move over the bridge by itself.

Then we're gonna put weight on it and then we're gonna try to crush it.

How's that sound?

- Yeah.

- Yeah.

- (laughs) So let's get to it.

You're gonna start by doing a drawing to map out what you want to build, and then we're gonna start building.

(upbeat electronic music) After the design is created, the crew builds the decks.

- Wow.

- They build the sides and then connect everything together with tape.

(upbeat music continues) These look amazing.

You built your bridge.

It looks like a truss bridge.

I love it.

- [Both] Yeah.

You built a bridge.

It looks like a truss bridge.

Looks fantastic.

- Bring on the pennies 'cause I'm an engineer.

(triumphant fanfare) - And let's see if we can get it through.

I might have to help it a little bit.

(mimics revving) (mimics brakes) Right at the end.

Yes.

It fit.

Okay, so you want to test first?

- Sure.

Yeah.

- Here's what we're going to do.

We're going to take an empty container and I'm going to put pennies into it.

(rolls of pennies clacking) (upbeat music) - I think my favorite part of doing the whole thing was like, me and Collin just like putting our heads together and seeing what we could come up with and like, putting together our ideas and seeing, like brainstorming.

- [Mr.

C] I'm very impressed.

(info panel bleeps) - Our bridge got this.

It's got this.

(pennies jingling, scraping) The X at the bottom is helping a little bit.

- Okay.

I think we can say that that's a lot of weight.

- Yeah.

- We will get that measured, but we have two tubs of pennies that your bridge can hold, and the monster truck.

Excellent.

Great job.

Give yourselves round of applause.

Nice.

- Thank you.

- All right, boys, you ready?

- Yep.

- All right, here we go.

It can roll across.

(laughs) But can't it hold pennies?

- We ran into a hiccup in the middle, which made it shorter than the nine and a half inches that was required.

So last minute changes, we had to make an extra deck.

(pennies clinking) - All right, it's flexing.

It's flexing.

Well, it's about to go, and I want to say one thing before it happens.

You guys are fantastic engineers.

Did you have fun today?

- [All] Yes.

- So, I am gonna challenge all the kids at home to build a bridge that meets all the requirements so that you too can design and engineer.

But most importantly, I have to ask a simple question.

What time is it?

- [Crew] Science time.

(pennies clattering) Oh!

(laughs) Oh, that was awesome.

That was awesome.

Great job.

High five.

The timing could not have been better.

Let's build a da Vinci bridge.

(bright music) - Leonardo da Vinci, the great inventor, invented the concept (notebook jingles) of the self-supporting bridge in the 15th century.

His design relies on interlocking wooden beams to create friction and compression.

What's amazing is that you can build it without any nails or fasteners.

Grab some pencils or pieces of wood and follow along to create your bridge.

- The da Vinci Bridge.

I challenge you to make one too.

Look how strong it is.

- Once you have it built, add some weight to test it.

Try pushing harder, Mr.

C. It stands with ease and is as strong as can be.

- Building bridges, building bridges.

They reach from side to side.

Arches, beams, and even trusses across them, we can drive.

Today was such a fun day.

Isn't it amazing that you can take a simple piece of paper and just by changing the shape, it increases its structural strength?

Could you build a larger arch bridge than Mr.

C?

Or a stronger bridge with a different type of pasta?

That activity was pasta-riffic.

I think my favorite type of bridge is a suspension bridge.

It lets me hang out with my crew.

(chuckles) Oh, do you have a favorite bridge near where you live?

Try building a replica model of it and test its strength.

Give it a try.

(truck whirring) - Oh, wasn't that awesome?

(crowd exclaiming) My car went over this bridge.

This is a suspension bridge that I built.

I've been working on this for a couple of weeks and it's taken a lot of time to build it.

In fact, it was really challenging because these cables here hold the strength and help the deck get pulled up when we add lots of weight to this.

Now I'm not gonna destroy this right now like we did with our pasta bridge, but I think this could hold a lot of weight.

Today was awesome.

We traversed ravines, we traversed rivers, and we focused on building bridges that were able to get us from one point to another.

We used different materials like sugar cubes, paper, and also pasta to build a bridge.

And regardless of the bridge that we built, we learned some things about how to connect things and how to make it structurally sound because the structure is so important when you're building a bridge, whether it's a beam bridge, an arch bridge, a suspension bridge, or even a truss bridge.

And all of those things that we did today were so fun, but it reminded me that we need to put that information into our "DIY Science Time" notebook.

This thing here allows us to keep track of all the bridges we built and all of the weight that they could hold, whether it's 15 or 20 pounds of pennies or 100 pounds.

The DIY Science Time Notebook (piano keys clang) is something you should download to help you keep track of all of your information.

What an amazing day.

We had so much fun, we learned so much, and I can't wait to keep exploring different types of bridges in my neighborhood, in my neck of the woods.

It's awesome.

I want you to keep learning.

I want you to keep exploring.

I want you to keep having fun, and I want you to remember that science is wherever you are.

Take care, everybody.

Bye.

♪ It's science time ♪ (upbeat music) - Oh, it's gonna work.

It's gonna work.

- On the market for $1 billion.

- Yeah.

- Who wants to buy?

- Oh.

(laughs) (upbeat music continues) Oh.

(grunts) ♪ It's science time ♪ - That... (gibbers) Yeah.

My pasta saved the day.

Yeah!

♪ It's science time ♪ - Tear that bridge down!

♪ For all the kids, it's a pasta truss bridge ♪ Get the meatballs.