(upbeat music) - [Mr C] What time is it?

- [Kids] It's science time!

♪ Science, science, science time ♪ ♪ Let's all just stop and just unwind ♪ ♪ One, two, three, four, here we go ♪ ♪ Learn so much your brain explode ♪ ♪ Lessons so cool, so fresh ♪ It's so great 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 best believe it ♪ Explore and learn new things ♪ Come and join me please - I'm Mr. C, and this super smart group is my science crew.

Lyla is our notebook navigator.

Alfred is our experiment expert.

Rylee is our dynamite demonstrator and London is our research Wrangler.

Working with my team is the best.

It makes learning so much fun.

Actually, you should join us.

Today, we're building a solar balloon.

What time is it?

- [Kids] It's science time!

(space music) - Oh my goodness.

If you're just tuning in I got an email from one of my science fans.

Let's check it out.

Dear Mr. C, my name is Jonathan and I love hot air balloons.

I have a great idea for your next DIY science time.

My mom and I have been learning about hot air balloons and also found something called a solar balloon.

We're not quite sure what it is or how it works but you should check it out.

Your science pal, Jonathan.

A solar balloon, a solar balloon.

This is what we're building today.

That's right.

We are building solar balloons.

(laughs) Yeah, it's actually a pretty serious topic because it uses the sun's energy to power it.

And how are we gonna do this?

Well, we're going to build it right here right now together because you are officially one of my crew members now.

You're part of the science crew.

Tun-da-da-daah!

Tun-da-da-daah!

And that's what this is all about.

We're going to learn together.

We're gonna talk about the science together.

And most importantly, when we're done, you're gonna have a solar balloon that you can take outside.

You can fly high up in the sky and explore the scientific concepts that make it work.

- [Alfred] We're going to sort through this build today and we'll need a few simple materials, tape, strings, scissors, and garbage bags.

- As you can see our materials today are super ultra simple.

Hopefully most of you have these things in your house right now.

So you can build this with me.

You've got these garbage bags, the tape, the string and scissors.

And I want to say something right away.

If you don't have one of these things that looks exactly like mine.

That's okay.

That's the whole point of what we're doing.

We're building a solar balloon together but they're all going to be slightly different because all of us are using different materials.

And most importantly, we're all building them slightly differently which ultimately impacts how they fly.

That's what's cool about science.

I can do it one way.

You can do it another and our results might be the same or they might be different.

This is a 30 gallon garbage bag.

It's huge.

And when I went to the store what I looked for was a really thin bag.

I wanted to get a thin bag because the thinner the bag the lighter the material, and hopefully more easily it can fly up into the sky.

Now, when you're looking for bags at the store they're gonna say something like mill, M I L. This is the thickness, the smaller the number, the thinner the bag.

The bigger the number, the bigger the bag.

But it's teeny tiny because garbage bags are super ultra thin.

But you want to get the thin as possible.

And I actually just kind of felt it to see which one I thought felt thinnest.

And boop, it was the thinnest.

Also another thing is you might not have the same string or the same tape.

Now this is masking, is this masking tape?

Yeah, packing tape.

This is packing tape.

So it's a really wide piece of tape.

And it's going to allow me to easily cover the seams of my garbage bags when we start to build.

If you don't have it that's okay.

And what we're doing is we're ultimately starting to talk about this thing called variables, variables.

Variables, variables are those things in an experiment that can be changed.

And when you change a variable the outcome of the experiment may also change.

For example, you can change the size of the garbage bag, the color of garbage bag, the number of garbage bags, the type of tape we're using to seal the seams or even the type of string we're using to tether the balloon.

When scientists change a variable they change one thing at a time.

This allows them to see if changing that one variable impacts the results.

(shuffling noises) Woo wee.

I'm looking for my most valuable tool.

My science notebook, that's right.

This right here is where I put all of my information, my research, my data, the results.

This is what keeps me on track when I'm doing science and all good scientists record their information separately so they can come back to it and check it out at a later time.

Let's take a peek to see what's inside - [Lyla] A science notebook is a tool that every scientist should have, and it gives us a place to record all of our learning.

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

A science notebook allows us to go back and review all 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 the screen like this it's a reminder that this is a good place for us to jot down new information.

You can see I've already added a title and the list of materials for today's activity.

Our crew is still going to have lots of information to collect and organize as we go through the experiment.

So keep your notebook handy.

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

If you don't have a science notebook yet download a copy of Mr. C's science notebook from the website.

- [Mr. C] First things first, we need to pull seven of these garbage bags so that we can use it to build the body of the solar balloon.

(upbeat music) So now that we've pulled our garbage bags we have them placed into three different sections.

Section one, section two, section three.

Section one and three each only use one bag and section two uses five bags.

How does this thing actually work?

Check this out.

Air is everywhere and it's floating all around us.

A solar balloon takes a long piece of plastic and captures the air on the inside.

When the sun strikes the black bag, the black bag begins to absorb the heat energy from the sun.

The heat energy is transferred from the black bag to the air molecules on the inside.

As those air molecules gain heat energy they begin to move around and bump into each other more and more rapidly.

As they begin to move around we want more space and they want to spread out.

This causes the air on the inside of the solar balloon to expand.

And as it expands, it becomes less dense than the air on the outside of the bag, because of this it's actually able to float off the ground and up into the air.

Now that you actually know how the solar balloon works it's time to start piecing this together.

This is actually where all the fun begins because this is really also the trickiest part.

I'm going to move my bags out of the way, just a little bit because I'm going to need lots of space.

You're going to also need lots of space to make this work.

Because when we open up these garbage bags, it takes up a lot of area.

So we're going to take this first bag and we're going to open it up.

But before I do that, the first bag, the handle, we're going to leave alone.

It's the bottom part that we want to cut off so that we can make this tube and connect it with the tape.

So we're going to cut this part off bag number one.

Now that I have the first bag cut the bottom of that I can discard that for now.

Bag number one is ready.

We're actually going to cut bags two through six the same way.

And for those bags, we cut off the top and the bottom (upbeat music) That is exhausting.

We've got one more bag to go and that's bag number seven and bag number seven is cut differently than the other bags, because this is going to be the last bag of our solar balloon.

We're going to keep the part that's sealed from the factory here and we're just gonna cut off this top handle.

And now, and now doing all that cutting sure does make someone thirsty.

That's why I use water H2O to quench my thirst not just for hydration, but also my thirst for knowledge.

(sip water) Most importantly, we can probably use water to talk about how those molecules are moving inside of a solar bag.

(upbeat music) - [Rylee] Air molecules are transparent, which prevents us from seeing them.

Just like the air inside a solar balloon water molecules are in constant motion.

If we use a cup of water, we can see how molecules act when they have different amounts of heat energy.

The first cup is filled with hot water from the faucet.

The second cup is filled with ice water.

We will carefully place one drop of blue food coloring into the cold water and one drop of red food coloring into the hot water at the exact same time.

Three, two, one.

Oh, wow.

You can see the difference right away.

The hot water spread the food coloring around much more quickly because the hot water has more energy than the cold water.

Those molecules are bumped against each other more rapidly whether it's the water molecules in the cups or the air molecules and the solar balloon we can see that more heat energy causes the molecules to act differently.

- [Mr. C] What I love about that experiment is the food coloring actually allows us to see the energy that those water molecules have.

It's pretty cool.

All right, let's get to building this solar balloon.

First things first, we need bag number one, and we need bag number two.

So I'm gonna move this stuff out of the way.

So we have lots of space to work.

(upbeat music) (laughs) I'll pick that up later.

All right, so instead of opening up this bag and whipping it open what I'm going to do is I'm gonna carefully unfold it.

Maybe.

There it is.

I'm gonna unfold this and lay it out nice and flat.

After it's nice and flat I'm gonna take bag number two and remember bag number two has both ends cut off of it.

I'm gonna unfold this the same way.

(unwrapping bag) Where is that?

There it is.

And I'm gonna lay back number two right next to bag number one.

Now, in order to get this to seal properly what we're going to do is we're going to lift and open the bag up very carefully.

It's kind of hard to see because they're black bags.

And when we overlap them, just to make sure that you get the entire seam covered.

Now you're gonna take this bag and slide it about an inch into the other bag.

So right here, we have our seam.

So I'm gonna get out my packing tape.

And if you have another set of hands in the house or a friend that's helping you.

This is a good part to get some help with.

What I'm gonna do is I'm going to put one long piece of tape over this seam.

(pulling tape noise) Perfect.

And what you do here is the seam is right here in the center.

And I've got all of this tape covering that seam up so that it's not going to unravel or have a hole in it right at the seam where air can escape.

(upbeat music) I'm gonna take this piece.

I'm just going to fold it over to the back.

And now that I have this side taped, I'm gonna lift the whole thing up and flip it over.

I'm gonna repeat this on the backside as well.

Pull this piece over, pull this piece over and now we have bag one and bag two connected.

So I have bag two and now I need to connect it to bags three, bags four, bags five and bags six.

Those are in the middle parts of our solar balloon.

So what I'm gonna do is I'm gonna have you watch a video while I am working on taping bags two through six together.

- [Alfred] Vacuum pumps are another great way to explore and learn about air.

It looks like Mr. C is putting a partially inflated balloon into the vacuum chamber.

Once it's turned on.

(machine noise) Oh wow.

This is so cool.

The vacuum pump is pulling all of the air out of the vacuum chamber because the air is being removed from the chamber.

It allows the air molecules inside the balloon to spread out.

And look!

When he lets the air come back into the jaw the balloon goes back to it's original shape.

Looks like he's going to try some marshmallow.

(machine sounds) Oh, that's awesome!

Did you think that that was going to happened?

And now, shaving cream.

What is that going to be?

(machine sound) Oh wow!

Whoa!

The crew is going to love this.

Seriously, how cool is that?

Here's the deal, the vacuum pump allows us to see that there's actually air inside the object, as the pump pulls air out of the chamber the air molecules in the object are able to expand, pretty cool, right?

(giggles) - [London] Here's something cool I found while researching.

The first transparent tape was invented in 1930 by Richard Drew.

It was called scotch tape.

- [Mr. C] While you guys were watching that, I was working on bags two through six and now we have our seventh and final bag to add.

Remember, this is the bag that we cut off the handle and we left the bottom intact so that it creates a seal for our solar balloon.

Let's do this last bag really quick.

(upbeat music) Before I take my last piece, I wanna say it's really important that when you're doing this you wanna use a flat surface, why?

So that you remove as many of these crinkles so that the tape can lie down flat and make a really, really good seal.

Anytime you have something that is kind of bumpy or in the way, it gives the air opportunity to escape, a place for it to come out.

And that's what we're trying to avoid 'cause we wanna capture all the air on the inside.

So it heats up and expands.

Here we go, our last seam of the day.

(tape sound) Flip it over to the backside and we are going to be finished here in just a second.

Oops!

Yap, I got a little piece here that's folded.

So I'm gonna try to fix that.

There we go.

We did it.

We did it.

We combined our seven bags and now we have a solar balloon that we have to take outside to fly.

Now here's the thing, we're gonna go outside and take this on our flight.

You're gonna want to take your long, your string.

And you're gonna want to bring along the tape, just in case you get a little hole or a puncture from one of the blades of grass.

That way we can fix something when we're out at the park or wherever you decide to fly this.

I think the only thing we need to do now is listen to a little song about heat transfer while we get ready to go outside (upbeat music) ♪ From hot to cold ♪ From hot to cold ♪ Heat transfer goes from hot cold, from hot cold ♪ ♪ From hot to cold, from hot to cold ♪ ♪ Say what?

♪ Heat transfer goes from hot cold, from hot to cold ♪ ♪ From hot to cold, from hot to cold, from hot to cold, ♪ ♪ Say yeah ♪ Heat transfer is really neat ♪ It almost goes from hot to cold.

♪ ♪ You'll always remember this could be easy ♪ ♪ Even when you're getting old ♪ When you go out to dinner if you want food ♪ ♪ That is searched super real hot ♪ ♪ But if you wait too long to eat ♪ ♪ Oh you'll be so sad with what you got ♪ ♪ See what happens it's really easy ♪ ♪ The food is sitting out and touching the air ♪ ♪ The heat from your food's not disappearing ♪ ♪ It's being transferred to the air ♪ ♪ 'Cause heat transfer is really neat ♪ ♪ It always goes ♪ From hot to cold, from hot to cold, from hot to cold ♪ ♪ Say what?

♪ Heat transfer is really neat ♪ It always goes from hot to cold, from hot to cold ♪ ♪ Say yeah ♪ It's summer time and you're at the pool ♪ ♪ Jumping off the high dive ♪ Once you hit hat cool water ♪ It feels like you're frozen alive ♪ ♪ See what happens ♪ It's really simple ♪ Your body has a warmer temperature ♪ ♪ 'Cause once you touch that cooler water ♪ ♪ It's taking your heat energy for sure ♪ ♪ Heat transfer is really neat ♪ It always goes from hot to cold, from hot to cold ♪ ♪ Say yeah.

♪ Thermometer is a tool we use to measure heat energy ♪ ♪ It measures particles movement ♪ ♪ They're moving endlessly ♪ When molecules gain heat energy ♪ ♪ They move around faster ♪ When liquid expands and the temp goes up ♪ ♪ On the thermometer ♪ 'Cause heat transfer is really neat ♪ ♪ It always goes from hot to cold, from hot to cold ♪ ♪ Say yeah ♪ Heat transfer is really neat ♪ It always go from hot to cold, from hot to cold ♪ ♪ Say what?

- [London] Did you know that the first hot air balloon ride occurred on September 19th, 1783.

The flight lasted 15 minutes and had three very special passengers, a sheep, a duck and a rooster.

- [Mr. C] All right, so we have our bag belt and we're outside.

What we're going to do is we're actually gonna take the wind to fill up our bag, right?

So, our solar balloon is currently empty.

We're gonna get a whole bunch of air on the inside of it and then we're gonna tie this, shut.

(upbeat music) All right, so now that we have it almost full, let a little bit more air in, I'm gonna pull it tight.

(laughs) Don't hit the mail box, no.

And that is a solar balloon.

Pretty awesome, right?

This only took 20, 25 minutes to build.

And now it's just so much fun.

Go outside with a friend, bounce it around, make sure you tie it so It doesn't float away or get caught up in the wind or up in a tree.

Yikes!

Oh, hey everybody.

Welcome back.

Wasn't that awesome?

The solar balloon literally lifted off the ground and floated up into the sky.

It worked just like we thought it would.

That heat energy from the sun was being absorbed by this bag, that heated up the air molecules.

And because of that, it became less dense and it was able to float up in the sky.

However, science experiments don't just end with it working.

How do we make it better?

Can we add more bags?

Does that improve it?

What if we use a different tape that's not as heavy?

Would that change the flight?

Remember that's why you have your science notebook so you can take notes, make changes and keep track of whether or not those changes impact the results of the experiment.

- [Lyla] Our crew has been in the swing of things.

Keep taking notes as you change things so that you're able to go back and see what works best.

The more you use the science notebook the better you'll get at taking notes and recording data.

Remember, you can hop online and download a printable copy of the science notebook we use here on DIY science time.

- [Mr. C] Most importantly, keep learning, keep exploring, keep having fun.

And remember, science is wherever you are.

Until next time, have a great day.

Bye.

(upbeat music) ♪ It's science time ♪ It's science time Oh, sorry.

I'm looking for my science notebook.

Most important tool of all my handy-dandy science notebook.

Look at it right here.

That's right.

I'm looking for my most valuable tool.

Here it is, most important tool of all.

My science notebook.

(machine sound) (paper rustling)