Support fo Curious Crew is provided by MSU Federal Credit Union, offering a variety of accounts for children and teens of all ages while teaching lifelong saving habits.

More information is available at MSUFCU.org.

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More information is available a ConsumersEnergy.com/Foundation.

And by viewers like you.

Thank you.

Hi, I'm Rob Stephenson, and this is Curious Crew!

Welcome to the show, everybody.

We always like to start every episode with a couple of discrepant events because discrepant events stimulate curiosity!

That's exactly right.

And I've got some fun ones for you today.

First, take a look.

I've got this board here and at the end of this board is a little pulley.

You're also going to notic that over the pulley is a string that goes all the way back to this cart and can roll.

Okay, Nicholas, I have a question for you.

I have a 200 gram mass.

What's going to happen if I hang this mass onto this string and let it go?

I think it's' gonna roll to me.

Okay, let's see.

Oh, my.

I got to put the brakes on that thing.

Okay, Let's say we wanted to keep that 200 gra mass on there, but we wanted it so the car stays still.

What do you think we could do?

Raise the board up.

Okay so we're going to try that.

Now, if I lift this to the board, I don't want it to slip.

So you'll notice we have another board clamped on the end, sort of establishing a pivot point.

Okay.

The other thing that we're to watch, though, is this protractor, because I would like to know at what angle we achieve balance.

So Milo keep a close eye on that.

I've got balance.

Now, where are we About on there?

About 20 degrees.

About 20 degrees.

Okay, so let's think about this.

What if, Milo, I substituted a 500 gram mass instead?

What do you think I might have to do with the ramp?

Make it steeper, Probably.

Okay.

He says make it steeper, like 40 degrees.

So.

Okay.

Oh, well, I'm nervous.

I'm nervous.

Okay, let's see if I can't let go yet.

I can't let go yet because it's going to fall.

I can't let go.

I can't let go yet.

I can't let go.

You're 40 right there.

Is it about 40 degrees?

Mm hmm.

Okay.

Interesting.

So that 500 gram mas could get balanced if we got it up to about 40 degrees.

Okay, I want to show you something else.

And it's going to deal with this little ramp right here.

Now, this one's really interesting because I can raise it up and even lock it in place.

I'm going to put this one just at about four degrees.

Okay And thank you for holding this.

I asked Nicholas, I said, can you hold my foam ring?

Julia, if I placed this foam ring on to this sloped ramp, what is going to happen?

I think it's going to roll down this direction.

Yep.

Beautiful.

Let's see.

I'm going to balance it.

Well.

Well, is this thing broken?

Well, let's try that again.

Okay, We're going to sit here and wait a minute.

Oh, okay.

That's perplexing.

I'm going to ask three of you to see if you can explain these phenomena by the end of the show.

You can use your background, knowledge, anything that you learn in the show as evidence to revise your thinking.

Who would like to do a little scientific modeling moments today?

Okay.

And then Annlyn, Xanna, Ekaansh, excellent.

Now, does anybody have a guess we're going to be investigating today?

What do you guys think?

Julia, what do you think?

I think we're going to be investigating ramps and another name for those?

Inclined planes.

Be sure to stick around.

You're going to discover th wonder of this simple machine, because not only are the advantageous, but entertaining.

Let' see if we can figure this out.

I noticed that the steepness of the plane doubled when Dr.

Rob switched to the greater hanging mass.

I saw that too.

I wonder if that mathematica pattern is predictable or not.

The perplexing plane is confusing.

Logically the ring should roll downhill.

I'd like to examine that ring.

Yeah, me too.

An inclined plane is a slanted surface, like a slope or ramp that can be used to move objects to a higher place.

Imagine you went to a football game and had seats high up in the stadium.

One way to get up there would be to climb up many stairs, which can get tiring.

Another option is to walk up a ramp or an inclined plane, although it might zigzag back and forth and cover more distance, it won't be as tiring because the change is more gradual.

Looks like you made it in time for kickoff.

So inclined planes ar one example of a simple machine.

And let's see if we can investigate to see how they can be useful.

Lake, I'm going to have you start.

What I'd like to do is we're going to walk up this ramp.

I'm going to spot you.

I just want you to walk along the ramp, walk along the ramp, walk along the ramp, and you can step off on the cement block.

That wasn't so hard, was it?

No.

Okay, let's make this a little bit more difficult.

I'm going to ask you guys, can you raise up this board for me?

Go ahead.

Lift it up.

And we're going to put another level.

We went from eight inches hig on this end to 16 inches high.

Okay, let's lower that back down and Lake, come back around here.

And let's do this again and let' see if you notice a difference.

Okay.

I'll spot you.

Excuse me, boys.

Thank you.

Nice, nice, nice.

Step down carefully.

And was it a little more steep for you?

Yeah.

So it required a little bit more work.

Now, that actually makes sense.

Here's why.

Not only are you propelling your body forward, you're actually lifting your body against gravity, but because it's nic and sloped, that's not so hard.

Now we're going to try something else.

You're probably wondering, why do we have gloves on?

Now it's because.

Oh, my.

I would like the two of you to lift up that block.

Go ahead.

Go on each side of it and just lift it up together On the count of three.

One, two, three.

Oh, that's awesome.

And lower it down.

That's got a lot of mass, doesn't it.

A lot of mass.

So, Milo, if we wanted to lift this block off the ground, how could we do it and use less effort?

I think we would use a string in this ramp to pull it up and have the blocks hold its energy.

So you probably notice I happen to have a cement block over there with a rope tied around it.

And we also have a ramp.

So we're going to try this.

Okay.

I' going to put this right on here.

And you grab hold of this thing and carefully, carefully, carefully drag it up there.

Okay, stop.

That was pretty good.

You made me a little nervous there.

You did that awfully quickly.

Milo what did you notice that time?

It was a lot easier.

You've got a mechanical advantage.

Here's why.

The ramp is holding the weight of the block so you don't have to.

You just get to pull it.

So it's a lot easier than lifting it straight up.

What if we had Milo do it one more time?

But this time we made the ramp way steeper?

How would that be for Milo?

I think it would be harder for him.

So the steeper the ramp, the more work that Milo is going to have to do.

But it is still easier than lifting it straight up off the floor.

The inclined plane?

This is a great, simple machine.

Inclined planes are terrific simple machines that can provide a mechanical advantage.

We saw how it was easier to pull the block up the ramp instead of lifting it.

People discovered the benefits of inclined planes long ago, and most people agree that the ancient Egyptians probably used inclined planes to move the enormous stones in the pyramids.

It is believe they pushed the stones up ramps on the outside of the pyramid to get them into place.

Even though they had to push the stones further, a ramp that wasn' so steep would be much easier.

Amazing!

Okay, so we saw how inclined planes can give a mechanical advantage, but let's see if we can actually calculate that.

Okay.

We've got a bag of marbles here.

And Nicholas, can you do me a favor?

Can you turn on that digital scale?

Okay.

We're going to want to put this on and see how many grams this is.

All right.

I'm gonna place that right on there.

And, Nicholas, you can tell me about what that is.

714?

714 grams.

Okay.

That makes a lot of sense to me.

Now, I don't know if you've ever seen this, but this is a spring scale and we're going to get the measurement this way as well.

And Julia, I want you to tell me, what is that coming in at about like 710?

Okay.

So pretty similar, right?

That does make sense.

Here' where it gets super interesting.

I'm going to place this on the ramp and we're going to drag it.

Oh, we saw that 700 grams over here, 700 grams here.

But, Ekaansh, I'm going to ask you to read out what you see.

And we're going to start off by elevating this up to about five degrees.

I'm going to start to drag it.

I'm going to pass it to you.

Go ahead, Ekaansh, you can drag it a little bit.

What are you seeing there as far as the number?

Whoa, it's from 700 and went down to 200!

Now, wait a minute.

Let's pause.

I want to see what happens if we go up to about ten degrees.

Okay, So we were 200 grams where we have now it's about 350.

Okay, Now, that's really strange.

Why would it be less than 700 grams?

I think it's less than 700 grams, because when we did it, we were pulling it up.

But now the board is actually holding it.

And so now we se the mechanical advantage, right?

The board is actually supporting the marbles.

Let's try this one more time and let's even go up a little steeper and see what happens here.

Ekaansh, what are we looking at now?

Still at around 400.

Still only 400.

So we can see that as the steepness increases, that mass increases as well, which makes sense.

Right.

So we thought about this advantage of things going up.

Now I want to start thinking about something going down.

Okay.

I'm going to place this block on here.

It is stable.

We are level, but there are forces acting on the block, Right.

Nicholas, what are some of the forces that are acting on this block right now?

Gravity is pushing it down to the normal force is pushing it up.

Excellent.

And those are balanced.

And so as soon as I start t raise this, I actually introduce another force.

What force?

Go ahead, Ekaansh, what force?

Friction.

Yes.

And in fact, we call this static friction because the friction from the board is resisting the particles with the block.

Now eventually, I can get it to slide.

But let's think about this.

If the normal force before was going up, as soon as I change the angle of the board, the normal force is now going on the same angle.

It's always perpendicular.

So the fun thing i we have gravity in normal force.

We introduce static friction but eventually gravity will win over both static friction and the normal force.

Pretty cool.

So whether going up or down inclined planes have their advantages.

Inclined planes make moving a heavy load much easier.

Have you ever seen a ram attached to the back of a moving or delivery truck?

The driver can cart heavy objects off the truck down to the ground or back up onto the truck.

Once you start to notice inclined planes are all around us.

They make it easier for someone in a wheelchair to get around.

They're great for loadin and unloading airplane luggage and they can be quite enjoyable on a playground.

STEM Challenge!

Now I've got a really fun STEM challenge for you.

We saw how when we put a block of wood on the ramp, that static friction kept it from sliding down.

So your job is to see if you can make a block slide more easily.

I like to call this the static friction reduction system.

You guys ready to get started?

Yeah.

All right.

Have fun.

My idea was to put, like, more felt on there so that there's less pressure on the wood underneath, which side do we want to put, like, more strapping or should all be even?

The materials we are using are sparkly bubble wrap and tape.

In this challenge we're using fiberglass matting on our wood block.

I think we should d these smaller pieces right here so they don't slip out from underneath.

I am folding the felt, then taping it together.

We did measurement and we cut the shiny bubble wrap and then we use that tap and then we folded it together just like gift wrap it again.

That only on the side.

Yeah, yeah, yeah.

But we should make it a bit looser.

How slidey is it?

We are wrapping the wood block with the fiberglass matting and then we're taking the ruler and taping that to the bottom of it.

Yay!

Our' is gonna look like a snowboard!

and you know how snowboards work.

That's pretty much it!

These are looking super interesting.

So here's we're going to do next we're going to move the tables out of the way.

We're going to bring in our ramp, set it to 20 degrees and see how well these slide.

We've got our inclined plane ready.

And you might notice I have it all marked of by centimeters in groups of ten.

So ten, 20, 30, 40, all the way down to 90 centimeters.

And then it picks up.

I don't know if these are going to run all the way onto the floor, but we want to be able to keep track of how far they go.

Okay.

So let's start with your team.

Like, tell us about yours.

What material did you use?

So we use fel and ours is a no-eared unicorn.

A no-eared unicorn.

Okay.

Do you think it's going to work pretty well?

Yes.

All right, let's give it a whirl.

Let's see what we got.

Okay.

I'm going to place it right up here and let it go at 20 degrees.

Is it going to slide?

Oh.

Oh, isn't that amazing?

We only ge we got about seven centimeters.

That's right.

That's right.

The unicorn.

The unicorn.

Okay, let's try another one.

So we've got yours What material did you guys use?

So we used fiberglass matting, but then we also taped a ruler to the bottom of it.

I love the ruler idea.

Okay, so let's take a look at this.

So fiberglass with a ruler on the bottom, how well do you think this one's going to slide?

It's going to go all the way down.

Oh, he's feeling fairly confident.

Okay, let's see.

We got it.

Oh, my.

And that ended up.

What did that end up?

I can't even tell.

That was really far over there.

190.

That ruler may have helped.

And what about this one?

What did you guys use?

We use shiny bubble wrap and our name is shiny, shiny.

Shiny, shiny.

So how do you think it's going to do pretty good?

All right, let's give it a whirl.

We'll put it up here and ther it goes.

There goes, there goes.

All right.

Nice job.

That one there.

Like 115 centimeters.

Well done.

Those were some great designs.

Try building your own static friction reduction system and see how low an angle you can get your object to slide.

The crew figured out how to get their blocks to accelerate by reducing the frictio between the block and the plane.

In 1604, Galileo Galilei also did some experiments with incline planes and acceleration.

He wanted to figure out what happen when things fall to the earth.

In his experiment, he rolled a ball down a ramp and calculated the distance i traveled for each unit of time.

He realized that all objects fall with the same rate of acceleration.

Now, that was a clever use of an inclined plane.

You know, some of my favorite activities include inclined planes.

Seriously, have you ever gone to an amusement park and or even a playground you get on a slide or the water park, You do a water slide.

Those are great incline planes, right?

Now, here we have another fun inclined plane.

Now, you'll notice we've got four cars here and I have the masses of each labeled.

So we've got some ones that are a little bit more massive on the outside a little less mass on the inside as it is right now.

There is a very gentle slope, only one block high.

Okay.

There's some potential energy here.

So if I push down on that lever, these cars are going to move.

What factors are going to contribute?

How far they're going to travel?

What do you think, Annlyn?

Probably mass and slope.

That makes a ton of sense.

I would like to se if we can get some of these cars to end in the target zone without hitting a wall.

Okay.

We're allowed to change factors.

Do you like one block higher Do you want to make it higher?

What do you guys want to I think to two blocks on.

Are you comfortable with that?

Yes.

Okay.

Let's see what happens.

You want to do a test run and see what we do with two blocks high?

Sure.

Okay.

And we're going to stay at about 60 centimeters to the target zone.

All right.

Let's see what happens.

Oh, there.

Oh, they all three hit.

And that one got a false start.

Okay, s we're going to bring these back.

We can change a factor.

What is another thing that we could manipulate in this variable?

Could we move the target zone?

Oh, oh, because we're only at 60 centimeters.

What would you guys like to do?

I can move the ramp back.

Okay, I'm good with that.

And so you want to try 70 or you want to go further?

75, 75.

Are you comfortable that 75.

75.

Okay.

75.

Oh, come on, Blue.

Oh, oh, that was kind of interesting.

That was kind of interesting.

Do you want to have a little bit more distance?

What do you want to do?

Yeah, I think we have a little bit.

Little bit more there.

80 to 80.

That's very precise.

We'll see if we can get one without a false start here for all the way around.

Oh, Blu doesn't want to play this time.

Oh, let' see if that one's going to go.

Oh, now that's kind of interesting.

So we sort of split the difference there.

Do you think we are too far?

How about 86?

Thereabouts.

Okay.

And then let's see.

We got push it down.

Push the whole thing down.

Oh, Oh, this is looking promising.

Oh, okay.

You are so close.

I want to go a little bit further.

We can estimate it.

Let's try right there.

Okay.

Oh, oh, oh, oh.

He's in.

You got one in.

That's why we help each other.

Go, go, go, go.

He was still in.

Oh, so you had one finally make it, though.

This one got pushed in by the blue car right there.

This is not as easy as it looks.

I've got one more thing that we're going to try.

And in each of these cases, we are talking about potential energy that is converting to kinetic energy.

Now, I'm going to place this car.

This one is about 36 grams about right here.

And I want you guys to point on this side how high do you think this ca will travel on the other side?

Point to where you think it' going to go there, about there.

Okay.

Watch this one close underneath all of yours.

Now, why is that?

Here's the crazy thing.

We are losing so much in friction with the wheels that no matter at what height we start, it will never get that same height again.

So inclined planes are grea at converting potential energy into kinetic energy.

Let's try one more time.

There you go.

Inclined planes are really helpful and engineers are using them everywhere.

As you're out and about, be sure to notice the ramps on sidewalks and trucks at skateboarding parks and handicapped access ramps throughout your community.

I'm especially grateful for inclined planes every time I drive over an enormous mountain and I switch back all the way up, I certainly wouldn't want to drive straight up over it.

Simple machines may be simple, but they sure are handy.

Are you curious about careers in science?

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And today I'm here with Dr.

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Cynthia, can you tell us what you do and where we are?

I'm an oral maxillofacial surgeon in m hometown of Jackson, Michigan.

So we pull teeth out for braces and we help expose teeth that are hidden in the bone or orthodontics.

People have lumps and bump that shouldn't be in their mouth or white spots or red spots o cancer lesions or pre-cancerous.

We take samples of that or take the whole thing out.

These are tools that will help go around the outside of the tooth and literally elevating our fanciest machine And technology in the office is our ICA.

It's a 3D scanner for scans of face and the oral cavity.

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And with the image, all the information, it's a 3D renderin that will put it back together and form the skull.

Dr.

Cynthi Rider gave me an implant of oral surgery knowledge.

Explore your possibilities!

And now back to Curious Crew.

So we know an object on a ramp experiences the force of gravit and a normal force pushing up.

But the normal force is always perpendicular to the ramp.

That's right.

And a steeper ramp also has less friction.

I wonder what would happen if we combine the masses.

I'm sure the ram would need to be even steeper.

I think Dr.

Rob must have done something to the ring in the perplexing plane.

I don't think it's balanced.

So have you had fun investigatin inclined planes today?

Yeah, I'm so glad.

Now we're going to take a look at these discrepant events to see what you could figure out.

I knew you would rise to the occasion.

So.

Annlyn What did you figure out about this inclined cart?

When the ramp is flat, the hanging force applies enough tension to the cart so it rolls towards the pulley.

And raising the ramp changes the net forces on the car, especially the normal force and the friction.

So the ramp has to get steeper to balance the hanging mass.

Okay.

And so we saw that we had to raise it up about 20 degrees for the 200 grand mass, but up to about 40 degrees for the 500 grand mass.

The other thing that we have to think about, just as Ekaansh was talking about, that normal forc is constantly changing as well.

Every time the ramp goes up, the normal force is perpendicular to the ramp.

So if we had a super steep ramp, the normal force is going like tha and it does reduce the friction as well.

And we would like to do that again, but this tim with both masses on the strings.

Okay, S you're going to have to help me.

So this is going to be like 700 grams.

Okay.

So if we have both masses on here at 700 grams, how steep is this ramp going to have to be?

We talked about it and we think it would be about 65 degrees.

Okay.

That's a lot.

All right.

We'll see if we can hold this steady and we're going to have to keep going up, up, up.

I'll take it from there, Ekaansh, and let's see if we can get that cart so it isn't moving.

Well, I think we got it.

And it's pretty close to 65 degrees.

So thinking about that mathematically, that kind of makes sense.

If we had mass of 20 degree and then another mass equaling 40 degrees, the sum of those brings it up to about 60, 65 degrees.

That makes a lot of sense.

Okay.

So what did you figure out about this perplexing plane, Xanna?

Well, we think you must have done something to the ring to make it roll uphill, when it should rol down the plane due to gravity.

So it must be out of balance.

Okay, let me see that, Nicholas.

So you guys caught me.

I got to tell you what I did here.

So this disc or wheel has very, very little mass, But you might not have noticed, but I have a little circle right there because I cut out part of the foam, and I inserted a weight.

Now, this i now completely out of balance.

If I were to try to balance this in the middle, it's going to tip where the weight is, Right?

So watch the trick.

I set this to four degrees and then Julia wisely predicted it should roll downhill.

But what she didn't know is I put the weight right up at the top.

So it's now changing the center of mass.

So as soon as I let go, the weight is falling to the earth and it rolls in the wrong direction.

So it does make for a very perplexing phenomenon.

Right?

So remember, my friends, stay curious and keep experimenting.

Get your curiosity guide and see more programs at wkar.org!

Support for Curious Crew is provided by MSU Federal Credit Union, offering a variety of accounts for children and teens of all ages while teaching lifelong saving habits.

More information is available at MSUFCU.org.

Also by the Consumers Energy Foundation, dedicated to ensuring Michigan residents have access to world class educational resources by investing in nonprofits committed to education and career readiness.

More information is available a ConsumersEnergy.com/Foundation.

And by viewers like you.

Thank you.

That was good, man!

That was good.

Just wait.

Just wait.

Get it.

Weight.

Ha ha ha ha.

Get it.

Weight.

So whether going up or down in Implying!

Implying forces because they're implied.

Thank you.

You read my mind.

Okay, here we go.

We're on it.

I was flowin, J. I was flowin, J.