Magical Forces? Or Science?

• Science
• Mathematics
• 6th Grade
• 6th,7th Grade

Forces and Motion

What do you already know about forces?
List a few things on a separate piece of paper.

Remember your reading on roller coasters? 

Now we're going to dive a little deeper to learn about forces and how to do some math calculations. Buckle up, or else you'll fall out!!

Use this image to answer the questions on the next few slides

When does the apple have a lot of potential energy?

1. when it's hanging from the branch
2. when it's falling from the tree
3. when it hits the ground
4. when I eat it

When does the apple gain kinetic energy?

1. when it's hanging from the branch
2. when it's falling from the tree
3. when it hits the ground
4. when I eat it

In case you were confused about those, let's review potential energy. What is potential energy?

1. the energy of an object in motion
2. the change in speed or direction of an object
3. the force that pulls objects toward one another
4. stored energy due to an object's position

So what's kinetic energy? and then watch the funny video on the next slide : )

1. the energy of an object in motion
2. the change in speed or direction of an object
3. the force that pulls objects toward one another
4. stored energy due to an object's position

What Did the Video Tell Us about Work?

1. You need mass and speed in order to do work

2. Work is measured in joules

3. To calculate "work" we need force and distance 

force X distance = work

Let's try an example: 

Danny hits the baseball with a force of 5 N. The baseball moves a total of 10 meters. What is the work? 

Answer

Since we know work is force multiplied by distance, we have to plug the numbers into the equation. 

5N (newtons) X 10M (meters) = 50 J (joules)

Your turn!
Hazel pushes the boat with a force of 15N. The boat travels 2 meters. What is the total work?

1. 0 J
2. 300 J
3. 30 J
4. 100 J

Here's a tough question: Nolan pushes really hard against a wall but the wall doesn't move. Has work been done? Explain your answer.

One more practice question:
Christine tosses a cupcake over the porch and you catch it. She threw it with a force of 10 N. The cupcake traveled 5 meters. What is the work?

1. 5 J
2. 15 J
3. 500 J
4. 50 J

Great work! Now we're going to talk about gravity.

 Gravity is keeping us from flying up into the air right now. This astronaut is experiencing the sensation of zero gravity. What did we learn about gravity in the reading on rollar coasters?

Gravity: what do you already know? Jot some notes down on a separate piece of paper.

Some Notes on Gravity:

1. All objects have gravity (the sun and moon just have more of it!)

2. Gravity depends on the mass of an object. The bigger the object, the stronger the gravity.

3.  The surface of the Earth is pulling you closer towards it as you gain more weight-- watch out!

Gravity is...

1. what causes everything to fall down
2. what helps planes fly
3. what causes everything to float
4. what the dentist finds in my teeth when I ate too much sugar

Take a look back at this picture from the beginning of the lesson

They're being pulled downward, probably after going up a big hill. What force is at work here? Why didn't they continue going up forever?

GRAVITY!!

When is a time gravity has acted on you? Tell me about it!

Summary of What We Learned Today: 

1. Potential energy  is the energy an object has before it falls

2. kinetic energy is the energy of an object in motion

3. work = force X distance

4. Gravity is the force that is keeping us on the ground

5. All objects have gravity; the stronger the object, the more gravity

You're all done for today! Great work! See you soon!  Love, Hazel

Images Cited

Adeline, Trevor. “Caiaimage." Getty Images, 2 Apr. 2020, https://science.howstuffworks.com/engineering/structural/roller-coaster.htm. (not intended for copyright purposes)

Photograph of Gravity cover. Warren Bros Pictures, 2 Apr.  2020,

https://www.imdb.com/title/tt1454468/mediaviewer/rm741451264 (not intended for copyright purposes)

Completed Check. Shutterstock.com, 2 Apr. 2020, https://www.shutterstock.com/search/completed (not intended for copyright purposes)

Tree with Apple. Lessonup.com, 2 Apr. 2020, https://www.lessonup.com/app/internetsearch?q=gravitational%20energy (not intended for copyright purposes)

Force Cartoon. Lessonup.com 2 Apr. 2020, https://www.lessonup.com/app/internetsearch?source=googleimage&q=forces (not intended for copyright purposes)

 

Videos Cited

Zhou, Hongjia. "eureka 9 kinetic energy." Youtube," 21 Nov. 2011, https://www.youtube.com/watch?v=BGmUVoX5s58

Crash Course Kids. "Defining Gravity: Crash Course Kids #4.1 " Youtube," 24 Mar. 2015, https://www.youtube.com/watch?v=ljRlB6TuMOU