[Alarm clock ringing]
Alright
Whoo!
[Explosion]
Oh, hello! [groan]
So happy to see all of you again and for our new friends
Science Explorers is a hands-on science 
program that's all about having as much fun learning as possible.
Now for friends that have attended Science Explorers before they know we offer our after-school clubs,
and I'm here today to tell you that once again we will be offering them this school year.
Now, they're gonna be a little bit different. 
Everything's a little bit different,
but what you're going to be able to do
is get the materials shipped to your home.
And then you'll get to work together with your classmates and one of our world-class instructors from the comfort of your home.
So, if you want to learn more about
that be sure to head to our website,
which I will insert right here.
Because today we are going to be talking about...
Force, and pressure, and other types of ways that things
 like to move.
So, let's talk about that first word: force.
Now, force is just a push or pull.
I know a lot of times in science concepts can be a little, you know, confusing.
But... a lot of times when you put those concepts in your own words you'll understand them much much better.
So, we know that force is a push or a pull, and we're going to talk more about force a little bit later.
Now, we know that we can use, you know, I can use my hands to push something over,
or I can you know pull this tablecloth off of there.
But can you use air to push or pull something?
Now, we know we can use air to, you know, 
push my  hair back.
[leaf blower]
But you can also use air to pull things along.
Now, uh, you may have seen this on the
side of the road.
When you see a bunch of leaves that are just, you know, just-
We're kind of getting to that time of year. It's beautiful!
You can use air to pull things along.
When you have a fast car, and that wind from that fast car goes by it pulls the leaves into the road.
And that's because of something called the Bernoulli principle.
Now the Bernoulli principle is all about how fast moving air has very little pressure.
Whereas, slow moving air, or air that's kind of still like the room, uh, I'm in.
Uh, it- that has a lot more pressure.
It's the same reason why when
you're opening a trash bag you don't [blowing air]
 to blow it up.
Instead what you do is you open it up, and then you use the air around you to fill it up
Because that air has more
pressure to it.
Another way to think about this
is, you know, you have fast moving air and it can pull things along.
So obviously you can use air to push a ping pong ball.
[Leaf blower]
But you can also-
That was loud!
You can also use a leaf blower to pull a ping-pong ball.
So, let me show you this.
So, you have right here my leaf blower, and I have
this little piece of plumbing pipe.
And what I'm going to do is I'm going to
put this on here.
Now, as the air is being blown out that
way there's low pressure right here,
and that high pressure is creating kind of like a gap that needs to be filled in.
So, the leaf blower- while it's like that- it's going to start sucking things in through here.
It's the same way that your like vacuum at home works.
So, when I turn it on and hold the ping pong ball right here-
Whoopsy daisy!
When I turn this on, and
I'm holding the ping pong ball right here...
[Leaf blower]
What happens is the fast-moving air
creates a opening with the low pressure right here, and pulls things in.
When you have your hand up against this you can feel it pulling on it while it's on,
and that's what sucked up the ping-pong ball.
But, as Science Explorers the way we like to have fun: bigger... better!
So, instead of just getting one ping pong
ball at a time and just puttin' it right here
I built a little contraption that loads
them into the barrel.
I guess you could kind of say.
But, you have ping pong balls that are gonna be coming down through there.
So, when I plug it in and remove the safety pin right here the ping-pong balls will be fed into a low pressure front
where the high pressure front, that the ping pong balls are coming through, are gonna suck them in and-
I don't know!
Let's just, uh, let's see what happens.
[leaf blower]
It works.
So, as you can see,
the experiment was a success.
We were able to use Bernoulli's principle that says:
that when you have fast-moving air it's going to want to pull in other things along with it.
Now, one way that you can use Bernoulli's
principle at home to make something cool,
without having to go to the hardware
store several times.
Is- all's you'll need uh to do this is
a straw and a cup of water.
And what we're going to do is we're
going to make something called atomizer.
An atomizer
is what is used in a...
Spray bottle!
There we go, can you- ope!  I got the light!
But you can see the way that it sprays the water in a nice fine mist,
and the way it does that is by having
fast air move over the top of a tube that has water in it.
Now, instead of, uh you know, having that fast-moving air fling ping-pong balls at me.
What it does is it atomizes or breaks it
up into small little pieces, uh, the water.
It breaks the water up into
tiny little particles.
Alright, and I need to use that water again. Alright.
Now the way you do this is you have your
straw;
you cut it in half like that, and then
you put the one... straw in the water.
Now this might take a couple tries.
We'll see how well it shows up on camera, but-
[air whistles]
Let's see if it looks better over this side.
[air whistles]
I'm getting my camera all wet.
But what you have happening here is when that fast moving air is moving over the straw
air is going down into the straw and kind of shaking up the water,
and then pulling some of that water back up
through the straw and out.
But that is how you make an
atomizer at home.
Now atomizers are used in spray bottles they're used
 in carburetors.
I don't think kids know what carburetors
are anymore.
Everything's fuel injected, am I right?
Now that is a fun little activity you can try at home,
but for this next activity, uh, I mentioned earlier that force- a push or a pull.
Uh, right now I want to talk a little bit
more about, you know,
how forces work and how things move.
So we're gonna cut to outside for this
scene because it was a beautiful day.
[whisper] Motion
Whoo!
[music]
[breathing]
Hello friends.
Give me a second with this guy.
The wind wants it to blow down.
[screen unrolling]
There you go that's how this guy works.
It's like a wind sail.
But today I have something very important to tell you.
I'm going to tell you about the three states of matter.
[cheering]
I mean the three laws of motion.
[applause]
Now the three laws of motion they were.
[crash]
That was, uh, Sir Isaac Newton's baby.
Now he wasn't just some old guy a long time ago.
He's one of themost famous scientists of all time.
And, oh, he was having a wild one constantly.
He was discovering things left and right, and what he loved the most was motion.
Three laws of motion: he was very proud of them, and they kind of relate to everything around us.
When I say kind of, I mean it literally does apply to everything around.
It's about how things move and the motion of them- ah!
There you go.
You know, the way things move,
 the way things interact with each other,
and the way that the world...
works.
So, there's three laws of motion.
and the definitions are:
The first law of motion is...an object in motion will stay in motion unless acted upon by an outside force.
And a object at rest will stay at rest unless acted upon by an outside force.
So, you got your second law of motion now, and that's force equals mass times acceleration.
And what that means... we'll get to it.
And you have our third law of motion.
For every action there is an equal and opposite reaction.
[breathing]
Whoo!
So definitions in science and a lot of
other studies can be intimidating sometimes.
You know, it's- they can be, uh, long and confusing.
Uh, but what I like to do is put them into
my own words,
and kind of apply them with what I  have in front of me to help me get a better understanding of how it works.
So, let me see what I got in front of me uh... let's see.
Alright now that I got my
favorite beach ball
we're gonna talk the three laws of motion, but we're gonna be using terms that we understand.
So the first law of motion; let's go over that.
An object in motion stays in motion unless
acted upon by an outside force.
An object at rest
stays at rest unless acted upon by an outside force.
So all that means is things will keep going...
until they're stopped.
And things will stay stopped
[grunt]
Until they get going.
Alright, the second law of motion: force equals mass times acceleration.
Now, mass is how big and strong something is,
and acceleration is how much something's speeding up,
and force is about how powerful-
 how overall powerful something is.
So, to measure my force without any acceleration I'm just gonna use how big and strong I am and push.
And that's a good measure of how powerful I am without... acceleration.
When I add acceleration  to my force... that means I have to get a running start to push this guy.
Alright. Hey, how you doing?
And you can see it goes much further.
Now, that brings us to our third, and my favorite, law of motion.
For every action there's an opposite and equal reaction.
So, when you throw something up,  it comes down.
So, when I grab the beach ball...and I...
[cheering]
[crash]
It comes back down.
[applause]
So that's the third
law of motion.
Every action there's an opposite an equal reaction.
I broke my sunglasses.
Alright friends, I hope you enjoyed the lesson today.
You can try this at home with a smaller 
beach ball probably.
Whoo!
And then I said- Oh, hello! Uh, you're back. wonderful!
I hope you enjoyed that segment on the
three laws of motion.
Now what's really important in these lessons is that even though a scientific concept may sound, you know,
kind of complicated or hard to wrap your head around.
You can always understand  science when you put it in your own terms.
So we know how things move.
We understand the motion.
We also understand how the Bernoulli
principle can have fast moving air pull things back in.
So a really fun way to think about that
is with something like, uh maybe, an air cannon.
Now this right here is
what we call an air cannon.
An air cannon is one of these little toys.
Some of you may  have something like it at home.
It has a little bungee cord inside here.
So when you pull back on this...
It gets pulled back in and then forces the air through- it's got like a big bucket.
But it pushes the air through this opening
right here.
As you can see there's some air pressure
behind that.
Now what's even cooler is-
You can't see what the air looks like while it's moving because it's like air,
but you can use something to make the air, uh, 
easier to see.
Now, the best way in my opinion to
visualize how air is moving is with fog.
[fog hisses]
Stinky.
Now fog is a fluid it moves
wherever it's told to move really.
And what we can do is fill up
our air cannon with some of the fog.
So you can see how it moves,
uh, as it's being fired out of it.
Alright. So, let me fill this up.
[fog hisses]
Looks nice and full.
And you can see
as this settles...
That it makes cool little smoke rings.
It makes- they're like donut shaped.
And I need to clear this out because I can't
 see anything here.
You get fog donuts.
Now as this fog clears out and
potentially sets off the smoke detector.
The shape of our fog donut that shape
is called a torus.
Not a Ford Taurus, that's a car.
Torus is the name of a donut shape.
And as the air is moving the air that's in
the middle is... the fastest.
The air in the middle that's moving the
fastest is pushing forward and then kind of pushing things out of the way.
But much like our ping-pong balls when
they're off to the side they get sucked back in.
Here's something
I built to kind of, uh, visualize what i'm talking about.
You have  our little donut shape.
Oh! a little more fog.
And this is a torus.
This is our... torus shape,
and the air that's right here in the middle as that moves forward, that moves back and that's our fog.
So pretend this silver stuff is our fog.
As fast air is moving through the center
the fog is getting pushed out of the way,
but then coming back around and going through the center again.
And that's how you get that torus shape, that fog donut moving forward.
Because you have that fast-moving air in
the middle and then it keeps on getting the fog trapped inside of-
uh, you know, the Bernoulli's principle:
kind of pushing it up and then sucking it back in.
Now, I want to show you how you can make your own 
air cannon at home.
And all's you'll need is a balloon and a
plastic bottle.
So using your balloon, and your plastic bottle, and an adult to cut the bottom off of your bottle.
And what that's going to do is- you will
then have your bottle like this.
And then you just need to take your balloon like that.
And you can also use a funnel
instead of a bottle, but I like the bottle more.
But what you're going to do is- you see how I have the balloon folded like that...
Fold it up like that and then just cut the top off of it.
There we go you still want the widest part of the balloon to be below your cut .
Because then you're going to take this,
and be patient with yourself with this.
It's a little tricky, but you're going to
want to stretch the balloon over-
Let's get this like that.
Over the bottom of this, and it might be
nice to have someone hold this while you're doing it.
Might make it work a
little bit easier.
["Dr." Evan makes noises]
Just like that.
So you're gonna get it
onto your bottle like this.
You can also use some tape to
secure the balloon onto your bottle.
And that'll help it, you know, not come off.
Because I know it
can be a little tricky.
I had a hard time with it.
Alright, yep, just using this tape to secure your balloon to the bottle.
And then also you can use tape- you don't even need to tie the end of the balloon.
But you need to seal it up, and I'll just
use tape for this as well.
So you just take that and
just fold it over like that.
That'll make a nice seal.
There you go. Not like the artist Seal.
But this right here is your air cannon.
Let's see if I can fill this up
with some of the fog.
There we go.
You can see the way that it
moves... and-
Oh, gentler seems to work better for the-
There you go. You can actually really see that.
Let me get some more fog in there.
There we go.
You can see the way that the air cannon creates these lovely little fog donuts.
Or as we know, uh, as they're called:
Torus.
Now the way we like to have fun as Science Explorers is,
you know uh, go big or go home.
So you can make, uh, 
one like this.
Uh, I have my normal one that
ordered online,
but today I wanted to make a super big one, so...
I got this right here and as you can see...
It's the same thing as my
yellow one, the one I bought from the store.
I have a little bungee cord in
here,  and that is connected to that.
So when I pull back on that I get a lot of air moving right at my face.
And I can pull this back and hold it like that and...
There you go. Did you feel that through the camera?
I bet you did.
And...
a little bit dust in there, little
plastic flakes I broke off.
But let's see what happens when I fill
this up with fog.
Whoa!
Very nice!
Really fill it up.
There we go.
Oh yeah.
Perfect!
Pretty nice right?
So that's what I made.
I can't wait to have fun with it.
Uh, maybe I'll get my roommate with it later today, who knows.
But thank you so much for watching and being part of this.
I hope that you all have such a stellar school year.
Uh, again we have our online after school
clubs with all of the material sent to your door.
Be sure to sign up for that if this is the type of fun you like to have.
You can go to our website below,
but nonetheless thank you again
for joining us.
And as we say at Science Explorers:
 if it's not fun, we're not doing it!
Whoo!
Bye-bye!
