2013
May 17

Cowboy Coloring Page

by Hannah Holt »

12 comments


It’s been a busy week, and tonight I’m headed to the Society of Children’s Book Writers and Illustrators Oregon Conference.

Writing conferences rock. I love chatting with people who feel passionately about oxford commas and third-person-single-reference narration. Plus, SCBWI always brings in fabulous keynote speakers.

The theme for this weekend is Wagons Ho! On the Publishing Trail, so I’ll leave you today with a cowboy coloring page and poem:

Cowboy trail clean

Happy trails, buckaroos!


2013
May 01

Newton’s Laws of Cake (Law #3)

by Hannah Holt »

12 comments


Oh boy! It’s time for the last law.

Newton’s Third Law of Motion states that for every action there will be an equal and opposite reaction. In other words:

Newton’s Third Law of Motion Cake: If you push cake, it pushes back.

Now that may seem like a weird idea. How can cake push? It doesn’t even have arms.

Well, let’s look at Newton Bunny. Here he is skating on Galileo’s Pond:

Newton skating

What would happen if we placed a giant chocolate cake right in front of him?

Newton skating cake

SMACK! The cake hits him.

Now wait a minute! Does he hit the cake or does the cake hit him? The answer is both. It takes two sides to create a reaction. If Newton didn’t hit the cake, he wouldn’t put a dent in the cake. And if the cake didn’t hit him back, he would just somehow pass through it like it was a ghost-cake.

So Newton hits the cake and the cake hits him back. Like this:

bunny pushing cake

Newton is pushing a cake and the cake pushes just as hard back. So the cake stays where it is and so does Newton.

But cake is just cake, and eventually it reaches a point where it can’t push back any harder. What if Newton pushes cake beyond its pushing limit?

bunny pushing cake unbalanced force

Anytime there is an unbalanced force something changes to balance it. The extra force is converted into motion. In Newton’s case, he falls into the cake.

bunny falls into cake2

Uh, oh! Newton pushed too hard. He fell into the cake.

So if you push something, it pushes back, otherwise you would fall through it.

Here’s a little review. See if you can fill out these activity sheets:

skating bunny worksheet

wall pushing worksheet

(Answers: Top – any path is fine, but once the bunny hits the cake he will be forced to stop. Bottom – The bunnies on the left hand side of the page will push the wall over because the bunny is pushing harder than the wall pushes back.)

SNEAKY FORCES:

In my last post I mentioned we would be discussing sneaky forces. These are forces you can’t see. Newton’s Third Law says that every action requires a reaction. So if something changes (reacts), you need an action. According to Newton’s First Law of Motion, if you threw a cake into the air, it would keep sailing up, up, and away. But cake won’t do that. Eventually it comes crashing down to the ground. Splat! Even though you can’t see it, something is pulling the cake down. Do you know what it is? Which of the following sneaky forces do you think is acting on the cake in the air?

sneaky forces

Gravity is the reason a cake falls to the ground. Here are some other stories. See if you can identify the sneaky force at work.

1) A cake is sliding along a table. No one touches it, but it comes to a stop anyway. What stopped the cake?
2) Buster Bunny delivered a cake to his cousin in jail. He baked a saw into the cake. A police officer with a magnet took the cake away from him without touching the cake. What force took the cake?
3) A cake resting on ice is placed next to a fan. The fan is turned on, and the cake slides away from the fan. What moved the cake?

Here are the answers:

1) Friction, 2) Magnetism, 3) Wind

So there you have it. Now you know all about Newton’s Three Laws of Motion Cake. Here are the three laws in review:

Newton’s 1st Law of Cake: Cake on a plate will not get up and start moving by itself. If the cake is moving, it will keep going until something stops it.

 

Newton’s 2nd Law of Cake: If you want to punch a cake harder, you must either hit it with something bigger or punch it faster.

 

Newton’s Third Law of Cake: If you push cake, it pushes back.

And now for a really nerdy aside: I’m a civil engineer and my husband is a physicist. We were having a discussion/disagreement about Newton’s Third Law. Now my husband is the kindest man I’ve ever met, but he didn’t like the way I was treating Newton’s Third Law, so he said, “Well, you just don’t think about motion because you’re a civil engineer. Civil engineers never do any work.” I had to laugh because he’s right. The whole point of civil engineering is avoiding work… Work is Force multiplied by Distance (W = F×d), and civil engineers build stationary objects. We make things that bend an wiggle but hopefully nothing that moves too much. Movement is the domain of mechanical engineers. So civil engineers build airports and bridges, and mechanical engineers build airplanes and cars. Also here is a free body diagram of cake being eaten by an alligator.

alligator2

Don’t worry, my husband and I resolved our disagreement and the above is physicist approved.

Have fun with physics! And go smash some cake!


2013
Apr 25

Newton’s Laws of Cake (Law #2)

by Hannah Holt »

11 comments


So Newton’s First Law of Motion Cake is all about moving cake. Newton’s Second Law is about punching cake. Let’s see what we can learn about punching cake…

Newton Bunny is practicing for the World Bunny Boxing Championship (WBBC). His sparring partner today is cake. Newton needs to know how to punch cake as hard as he can.

rabit punching cake

The Second Law of Motion Cake tells us there are two ways to punch harder:

rabit punching harder

Since this is supposed to be a physics lesson for preschoolers (and preschool teachers probably don’t need a lesson on punching)… let’s look at this law another way.

Newton Bunny is racing his cousin Sheldon. Both bunnies must run through a giant piece of cake on their way to the finish line. Newton is speeding up and Sheldon is slowing down. Which bunny will hit the cake with more force?

Newtons Second Law

In this example the bigness (mass) of the bunnies is the same. But one bunny is speeding up (accelerating), while the other is slowing down. The accelerating bunny will hit the cake with more force and have an easier time making it through to the finish line.

Now here’s an example where the acceleration is the same, but the size of the animals is different.

Newton Bunny and his friend Helga Elephant are having a cake smashing competition. Who do you think will make a bigger cake splash?

jumping on cake

Obviously Helga will make the bigger mess. Even though both animals fall at the same rate (acceleration due to gravity = 32 ft/s² or 9.8 m/s²), Helga has the bigger mass. She will hit the cake with more force.

Now someone in the comments is bound to say, “ELEPHANTS AND BUNNIES DO NOT FALL AT THE SAME SPEED!” or “YOU SAID CAKES DON’T STOP MOVING BY THEMSELVES, BUT THAT’S WRONG!” or “WHO CARES ABOUT BUNNIES AND CAKES?”

Well, I can’t help with that last one. If you don’t like bunnies and cakes, there’s nothing I can do about that. However, the first two comments will be answered because there is one more Law of Motion Cake that we haven’t covered yet.

Stay tuned for Newton’s Third Law of Motion Cake, which I will dub… SNEAKY FORCES.

Wow, only one more law and then we have covered all three of Newton’s Laws of Motion. Someone needs to bake a cake!

Newton’s Second Law of Motion is usually summarized like this:

Newton’s Second Law of Motion: Force is equal to mass multiplied by acceleration, Force = Mass × Acceleration, or

F = m×a.

I summarized this law like this:

Newton’s Second Law of Cake: If you want to punch a cake harder, you must either hit it with something bigger or punch it faster.

To review Newton’s First Law of Motion Cake, click here.
 
To check out Newton’s Third Law, click here.
 
The Fine Print (and Vocabulary):
I want to clear up one more thing for teachers. In this post I tried to describe acceleration in kid friendly terms. So I describe acceleration using words like “faster” and speed by using words like “fast.” I wouldn’t push a young child to recognize the difference between speed and acceleration. The important thing is that a child sees how situations are changed by switching up time, size, and quickness. It’s less important to quantify these changes.
 
However, for your reference here are the differences between some of these terms:
Speed = how fast something is traveling, like miles per hour or meters per second. The car is traveling 50 miles per hour.
Velocity = speed with direction (This is the point of view… Is the car traveling 50 mph moving towards you (+) or away from you (-)?)
Acceleration = how quickly something is speeding up or slowing down, like miles per hour divided by the time it took to get going that fast (miles/hour²)
 
So…
Newton’s First Law…. Momentum = mass × velocity (remember, velocity is speed in a specific direction). It says things want to keep moving even after force is no longer applied.
Newton’s Second Law… Force = mass × acceleration (or mass × velocity / time). It’s how things get moving in the first place.

2013
Apr 17

Newton’s Laws of Cake (Law #1)

by Hannah Holt »

23 comments


The other day I was showing my husband our son’s preschool work and he remarked “Why is it always dinosaurs? Why don’t they have a week in preschool on Newton’s Laws of Motion or something?”

“Because,” I said. “Dinosaurs are something concrete. You can’t teach a four-year-old physics.”

But the more I thought about it, the more I realized I was wrong. Newton’s Laws of Motion are totally visual. Really there’s no reason why they couldn’t have a week on Newtonian Physics at pre-school.

Of course, I’m going to tell it through my favorite medium: cake! So here it is. Newton’s Three Laws of Motion Cake, for four-year-olds.

I’ll tackle Laws 2 and 3 a little bit later, but first let’s start with the first law:

Law #1: Cake on a plate will not get up and start moving by itself. If the cake is moving, it will keep going until something stops it.

Go ahead and test it. Make a cake. Put it on a plate. Watch it. Will it move if no one touches it?

Let me tell you a story about a cake I made and a rabbit named Newton.

Here is a nice pound cake with whipped frosting. I place it on a stool. I hope it stays there until after dinner. Hmmm… What are some ways you think this cake could move?

1 cake on stool

Oh no! Here comes one. That tricky Newton Bunny is going to steal my cake.

2 bunny and cake

Newton runs too fast. He does not watch where he is going. Look, Newton stops, but he does not hold onto the cake. Does the cake stop moving by itself?

3 Bunny steals cake walla

Nope. It keeps right on moving, until…

4 Bunny falls

Splat! The wall stops the cake.

Oh dear! I will have to make another cake. It’s a good thing I like making cake. Here is the First Law of Motion Cake told another way:

If cake is resting on a stool, the cake will not move, unless something moves it. Once the cake is moving, it will keep going until something stops it.

Here’s an activity page to test your knowledge of Newton’s First Law of Motion Cake:

Law of Motion 1 Activtiy Page

Did you put everything in the right order? (If you aren’t sure, check the order of pictures in the story above.)

That’s it. That’s Law #1.Only two more laws to go before you are a Newtonian Physics master. The first Law of Motion is summarized on other websites like this:

An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

-The Physics Classroom

 

Every object in a state of uniform motion tend to remain in that state of motion unless an external force is applied to it.

-Astrowiki

 

Basically what Newton’s First Law is saying is that objects behave predictably.

-Dr. Anne Marie Helmenstine (You can read more by clicking this link)

Coming up next, Law #2: How to Smash Cake.

And Law #3: When Cake Pushes Back.


2013
Apr 11

Life Scientist Paper Dolls

by Hannah Holt »

23 comments


My family recently visited the California Coastal Redwoods.

Redwoods

Walking among century old trees was a unique experience. It made me feel so very small and yet large with wonder.

One of the things that touched me during our trip was this: without the diligent work of a few passionate individuals most of these trees might have been lost to logging and development. In the picture above, perhaps my boys would have been standing at the drive through of BurgerMart.

A few dedicated people can make a difference in the world, and science is a great way to make that difference. So I put together these life scientist paper dolls about a marine biologist and a botanist visiting the northern California coast.

Life Scients Paper Dolls color  Life Scients Paper Dolls bw

Of course, no life scientist would be complete without a habitat, so I painted two.

Redwood Forest Habitat (for the botanist):

redwood painted values pushed1

Northern California Tide Pool (for the marine biologist):

tidepoolfinal

And here are the plant and animal identification coloring pages for these habitats:

Redwood coloring page  Coast coloring page

I’ve had this song stuck in my head all day. “Habitat, habitat. Have to have a habitat…”

Here are the pdfs for easier printing (click to download):

1) Life Scientist Paper Dolls in Color

2) Life Scientist Paper Dolls in Black & White

3) The Redwoods Coloring Page

4) The Tide Pool Coloring Page