♪ If you're looking for a show ♪ ♪ With a little less cat ♪ ♪ Where a dog is the host, where the action is at ♪ ♪ Then check out The Ruff Ruffman Show ♪ ♪ We're doing science, The Ruff Ruffman Show ♪ ♪ We got the skills, The Ruff Ruffman Show ♪ ♪ Or, you know, kinda, The Ruff Ruffman Show.

♪ The Ruff Ruffman Show!

With Blossom and Chet.

Yeah!

♪ ♪ (Ruff yawns) Oh, sorry.

I just get really sleepy every time I watch that boring cat channel.

The Ruff Ruffman Show's going to have way more awesome skateboard footage.

(screaming) Well, as soon as I learn how to ride this thing.

My skateboard vids are going to be so rad, everyone will be wanting one of these-- the Ruff Ruffman action to the max-tion skate pro plushie.

Nice job, Chet.

Check it out, Blossom-- press this button, and you'll hear me say cool skateboardy things.

PLUSHIE: I love you, Grandma.

RUFF: Ah, that's not quite what I had in mind.

Or wait-- it's perfect!

My grandma's birthday is today.

Now I can give her an action to the max-tion skate pro plushie.

Come on, Chet!

This is perfect.

I'm going to let go of this plushie, and it's going to roll like the wind right up to Grandma.

This camera mounted on action plushie's helmet will capture all the awesome action footage.

All right, release the plushie!

Go, Action Ruff, go!

Huh, not a lot of action there.

Why isn't it moving?

Oh, you think I have to push it?

Okay, here we go.

Go, Action Ruff!

Okay, that rolled about the length of three Chets from tail to nose.

I need it to go a lot more Chets!

I need it to go 15 feet exactly!

Ruffie, what are you up to?

Nothing, Grandma!

So how do I get my plushie to roll farther?

Maybe if I gave it a really big push.

(grunting) Ow.

All that did was make it go a little farther.

Didn't do great things for my nose, either.

(i-bone ringing) Hey, Ruff, it's Ellie.

And Zeya.

RUFF: Hello, Ellie.

Hello, Zeya.

Great timing, you guys.

I'm in rough shape here and could use some help.

It's kind of funny this is happening to you, because something similar happened to us yesterday when I was pushing Ellie in the wagon.

RUFF: Ooh, this seems like a memory flashback.

ZEYA: I would run and run and run and let go.

But she wouldn't go any further than just a few feet.

RUFF: Oh.

ZEYA: Until the hill.

ELLIE: Oh, I love the hill.

RUFF: Yay!

Your problem is, Ruff, is the ground is flat.

For something to move, it needs a push or a pull.

And you'll need to give the plushie a big push to make it all the way to Grandma's front door.

Which is hard to do on flat ground.

RUFF: Hold on.

How can it go downhill if Grandma's lawn is completely flat?

Ruff, you'll need to build a hill.

Like a ramp.

If it's high enough, the skateboard will get going really fast and roll all the way to Grandma's.

You mean with the right ramp I can stand here and still get my plushie all the way to Grandma?

Then here's what I need you to do-- figure out how to build it.

Are you up for it?

We're ready and willing.

Yeah!

Hey, Zeya, this'll make a great ramp.

ZEYA: Yeah.

RUFF: A little plywood there.

ZEYA: Tape measure.

RUFF: Oh, those bricks look like they'll be super useful.

(crunching) And we have a skateboard.

Thanks for the plushie, Ruff.

RUFF: No problem.

ELLIE: We have a four-foot-long board for our skateboard ramp.

And now we will measure out the distance to Grandma's house.

ZEYA: 15 feet.

My mom will help us stack the bricks.

The higher the bricks go, the steeper the ramp gets, the farther the plushie goes.

And I will keep track of how steep we need to make the ramp.

RUFF: Okay.

So the steeper the ramp, the farther the plushie goes.

Got it.

Makes sense, I guess.

ZEYA: First we'll try one brick.

RUFF: I just keep going back to how adorable that plushie is.

ELLIE: Four feet ten inches.

RUFF: All right, a little short.

Guess we've got to lift it up a little higher.

ZEYA: Now we'll try two bricks.

RUFF: Go, go, go, go, go, go!

Eight feet four inches.

RUFF: All right, we're getting a little closer.

Almost to Grandma's house.

ZEYA: Brick number three.

ELLIE: If one brick made it go almost five feet... RUFF: Right.

ELLIE: ...and two bricks made it go over eight feet... RUFF: Right.

ELLIE: ...how many feet do you think three bricks will make it go?

I predict 12 feet.

RUFF: Release, and... ELLIE: Wow, 12 feet!

RUFF: Wow, you were right.

ZEYA: Four bricks.

I think this just might do it.

RUFF: Four bricks.

This is a four-brick journey.

Go, Ruff plushie, go!

Yay, I'm at Grandma's!

ELLIE: Wow, we did it!

Yay!

ELLIE: It took four bricks to make the plushie travel 15 feet to Grandma.

This is great.

With this ramp, I don't have to pull or push the plushie at all.

It just moves by itself.

Well, not exactly.

The plushie can't move all by itself.

RUFF: Oh, really?

ELLIE: Remember before, when I said that for something to move, it needs a push or a pull?

What's pulling the plushie down the ramp is gravity.

Gravity pulls everything towards the ground, and it's what keeps you from floating away.

You can't see it, but it's always there.

And that's what's making the plushie move.

When you put the plushie on flat ground, gravity can't really pull it down further.

But when you put it on top of a ramp, gravity pulls it right down the ramp.

RUFF: Oh, I get it.

Makes total sense.

This is awesome!

Thanks to your testing and data collection, Chet and I know everything we need to know to build my ramp.

How's it coming, Chet?

Good luck.

BOTH: Bye!

RUFF: Bye, guys.

Grandma!

Prepare for something super cool!

All right, Chet, release the plushie.

Oh!

He's picking up speed.

There he goes!

Wow, the ramp is perfect, and the skateboard is going to stop right at my... (bird cawing) (Ruff screaming) That crow has my plushie!

I'll save you, plushie!

I haven't learned how to ride this thing properly.

(bird cawing) (i-bone rings) GRANDMA: Ruffie, you mentioned a super-cool thing.

Has it happened yet?

Ah, yeah, that might take a little longer.

♪ The Ruff Ruffman Show.

♪ Yeah!