Grade 4 TCI’s Grade 4 program includes four units. Each unit has a Science Journal, complete with hands-on investigations, text with notes, and checks for understanding.
Unit 2
Unit 1 Plant and Animal Structures 1 What Plant Structures Are Used for Support and Growth?
6 What Animal Structures Are Used for Support, Movement, and Protection?
2 What Plant Structures Are Used for Protection?
7 What Animal Structures Are Used for Reproduction?
3 What Plant Structures Are Used for Reproduction?
8 What Animal Structures Are Used for Sensing the
4 How Do Plants Respond to Their Environment? 5 What Animal Structures Are Used for Digestion and Circulation?
Grade 4
Energy Science Journal
Environment? 9 How Do Animals Respond to Their Environment? Performance Assessment: Designing a Legendary Creature
Unit 2 Energy 1 How Are Energy and Motion Related? 2 How Is Energy Transferred by Colliding Objects?
Performance Assessment: Creating a Safety Pamphlet
3 How Is Energy Transferred by Sound, Light, and Heat?
5 How Is Energy Stored and Used?
4 How Is Energy Transferred by Electric Currents?
6 How Do People Choose Energy Resources?
Performance Assessment: Designing a Safety Device
Unit 3 Earth’s Changing Surface 1 What Are Some Clues That Earth’s Surface Changes? 2 How Does Water Change Earth’s Surface? 3 How Does Wind Change Earth’s Surface?
Performance Assessment: Investigating Changes to the Appalachian Mountains 6 Where on Earth Are Earthquakes, Volcanoes, and Mountains Found?
4 How Do Living Things Change Earth’s Surface?
7 What Can People Do About Natural Hazards?
5 How Do Fossils Form and What Do They Show?
Performance Assessment: Developing Hazard Plans
Unit 4 Waves and Information 1 What Are Some Examples of Waves?
5 How Can Sound Waves Be Used to Send Messages?
2 What Are Some Properties of Waves?
6 How Can Patterns Be Used to Send Messages?
3 How Do Waves Affect Objects?
Performance Assessment: Developing a
4 Which Waves Travel Through Earth?
Communication Method Using Waves
Engineering
Name:
Grade 4 Bring Science Alive!
Unit 2
Energy Energy is all around us! Sometimes we use it to help us and sometimes it can cause us harm. Help teach students about how energy transfers from one place to another by creating a safety pamphlet about how bike helmets work and by creating a device that uses energy to keep you safe when riding a bike.
1 How Are Energy and Motion Related?.......................................6 2 How Is Energy Transferred by Colliding Objects?.....................26 3 How Is Energy Transferred by Sound, Light, and Heat?...........46 4 How Is Energy Transferred by Electric Currents?.....................68 Performance Assessment: Creating a Safety Pamphlet...............94 5 Is Energy Stored and Used?
........................................... 100
6 How Do People Choose Energy Resources?......................... 120 Performance Assessment: Designing a Safety Device.............. 138 Engineering
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Anchoring Phenomenon Think about this unit’s Anchoring Phenomenon: Bike helmets protect you. Complete the chart. • List what you know about this unit’s phenomenon. • Write questions you wonder about this phenomenon. Know
Wonder
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Unit Checkpoints As you complete each lesson, look for this icon learned in the lesson. Lesson
and return to record what you’ve
What I Learned
1 How Are Energy and Motion Related?
2 How Is Energy Transferred by Colliding Objects?
3 How Is Energy Transferred by Sound, Light, and Heat?
4 How Is Energy Transferred by Electric Currents?
5 How Is Energy Stored and Used?
6 How Do People Choose Energy Resources?
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Unit 2 Energy
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Using what you’ve learned, explain the unit’s Anchoring Phenomenon: Bike helmets protect you.
Claim
Evidence
Reasoning
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Unit 2 Energy
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Lesson 3
How Is Energy Transferred by Sound, Light, and Heat?
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Lesson 3 How Is Energy Transferred by Sound, Light, and Heat?
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INVESTIGATION
Observing Phenomena Discuss: Can you think of an example where the energy transferred by sound can be seen?
Observe this phenomenon: This car isn’t moving, but the woman’s hair is still blowing around.
Try It!
With your class, put a few grains of rice on a speaker. Observe what happens when you turn loud music on.
Think of what you already know about how factors such as sound, light, and heat transfer energy. Write questions you have.
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INVESTIGATION
Observing Energy Transfers In this investigation, you will observe several images and discuss some ways energy is being transferred in each image. Then, you will read each problem-solving scenario and come up with solutions.
Energy is transferring as the stove heats the air. The air is warmer near the stove.
Energy is transferring out of these people to the cold air, making them feel colder.
Energy is transferring to the snow from the air, making the air colder.
E
A
D
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Energy is slowly being transferred from the thermos to the air, slowly making the soup inside colder.
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Energy from the warm soup is being transferred to the woman, making her warmer.
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INVESTIGATION
What are some ways energy is being transferred by heat? Fill out the observations chart.
Where Is Energy Coming From?
Where Is It Transferring To?
Other Observations
It’s getting cold at night! How can these snow campers keep warm after sunset? Use your knowledge of how to maximize and minimize both energy in and energy out to find the best solution. Solution
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How does this affect energy transfer? Will this increase or decrease energy transfer?
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INVESTIGATION
What are some ways energy is being transferred by sound? Fill out the observations chart.
Where Is Energy Coming From?
Where Is It Transferring To?
Other Observations
The neighbors are complaining! How can these band members practice quietly? Use your knowledge of how to maximize and minimize both energy in and energy out to find the best solution. Solution
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How does this affect energy transfer? Will this increase or decrease energy transfer?
Lesson 3 How Is Energy Transferred by Sound, Light, and Heat?
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INVESTIGATION
What are some ways energy is being transferred by light? Fill out the observations chart.
Where Is Energy Coming From?
Where Is It Transferring To?
Other Observations
Drivers are having trouble seeing people in the dark. How can you make yourself visible to the drivers in the car? Use your knowledge of how to maximize and minimize both energy in and energy out to find the best solution. Solution
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How does this affect energy transfer? Will this increase or decrease energy transfer?
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INVESTIGATION
What are some ways energy is being transferred by heat, sound, and light? Fill out the observations chart.
Where Is Energy Coming From?
Where Is It Transferring To?
Other Observations
You have a headache! How can you find a dark, quiet, cool place to rest? Use your knowledge of how to maximize and minimize both energy in and energy out to find the best solution. Solution
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How does this affect energy transfer? Will this increase or decrease energy transfer?
Lesson 3 How Is Energy Transferred by Sound, Light, and Heat?
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INVESTIGATION
Vocabulary Match each word to its corresponding definition. Word Bank reflect absorb vibrate
1. To take in. 2. To bounce off a surface. 3. To quickly move back and forth.
My Science Concepts Reflect on your understanding. Draw an X along each line. Energy can be transferred from one place to another by sound, light, and heat. Sounds are vibrations in the air that can collide with an object and transfer energy. Energy carried by light can be absorbed by objects it hits, which transfers energy. Energy in the form of heat will transfer from an object with higher temperature to an object with lower energy. still learning
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Though you cannot see sound, you can still observe its effects. When the ground vibrates because of loud sounds, you are observing the energy transfer from the sound’s source to the ground. When metal wires in a toaster heat up, they start to glow. This is because the energy transferred as heat can produce light. still learning
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1. Sound, Light, and Heat Transfer Energy You know that when you kick a ball or throw a rock into a pond, a moving object collides with another object and transfers its energy. But energy can also be transferred without moving objects. Three ways that energy transfers without moving objects are when it is carried by sound, light, and heat. A sound starts when an object, such as a guitar string, vibrates, or quickly moves back and forth. The vibration causes nearby air to also vibrate. This vibrating air then makes surrounding air vibrate, too. Energy transfers from each area of vibrating air to the next. Energy transfers also happen when light carries energy. Unlike sound, light can move through empty space. This is why light can carry energy from the sun to Earth. Light can also travel through air. It moves energy away from its source in all directions. A lightbulb can light up an entire room because it moves energy in all directions around the room. Heat is a third way that energy transfers without moving objects. Your hand becomes cooler when you hold a cold cup of water, and it becomes warmer when you hold a hot cup of tea. These changes in temperature tell you that energy is moving because of heat. Energy is transferring from the hot cup to your hand. 54
Lesson 3 How Is Energy Transferred by Sound, Light, and Heat?
When an object, like a guitar string, vibrates, it transfers energy.
Heat is a transfer of energy when there is a difference in temperature. The energy can be transferred to other objects. This is why holding a hot drink can warm up your hands.
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Look closely at this photo. Label and describe three ways energy is being transferred.
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2. Sound Carries Energy All sound starts with a vibration. A soccer ball vibrates when you hit it. The floor vibrates when you stomp on it. Drums and guitars vibrate when you play them. What happens to energy when an object vibrates? Vibrations Cause Sound
When you pluck a guitar string, you transfer energy to the string. The string then vibrates and collides with the air that surrounds it. As it does this, it transfers energy to the surrounding air, which produces sound. The sound also carries energy as it moves through the air. Objects, as well as air, transfer energy when they collide with each other. In this way, the energy carried by sound spreads out away from the guitar string. You hear the sound when this vibrating air reaches your ear. A vibrating object loses energy as it produces sound, but this energy is not destroyed because energy is always conserved. The sound carries the energy away from the object that is the sound’s source. For a plucked guitar string, the string has lost all of its energy when it stops vibrating. That energy is not gone. Instead, it has been transferred to the air and other objects. 56
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All sounds begin with a vibration. When you blow into a clarinet, the air makes a reed vibrate, which then transfers energy to surrounding air. This produces sound.
A reed is a small piece of wood on the mouthpiece of some instruments.
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Sound Causes Vibrations
You now know that the energy of vibrating objects causes sound. But sound can also make objects vibrate by transferring energy. This is why when sound from vibrating air hits other nearby air, that air also begins to vibrate. The energy carried by the sound is transferred to more of the surrounding air. If you watch a concert with drums, you might feel the ground vibrating below you. Loud music in a nearby car can cause your car’s windows to rattle. All of these vibrations happen because the energy that causes the air to vibrate is transferred. It is transferred from the sound’s source to the ground and to the windows of your car. The transferred energy makes the ground and window vibrate. Again, when sound causes an object to vibrate, energy is still conserved. It is not destroyed and has simply moved from object to object. The energy moves from the sound’s source to the vibrating air that surrounds it. Then after the sound travels away from the source, the energy moves from the vibrating air to all the objects that the air is touching. In this way, sound carries energy and transfers it to different objects, such as your car windows. © Teachers’ Curriculum Institute
If you hear a loud sound, like the sound of these taiko drums, you can sometimes feel the ground move. This happens because energy from the sound transfers to other objects.
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Draw and label a diagram that shows how sound carries energy. Make sure these terms are used in your diagram: air, ear, energy, sound, and vibration.
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3. Light Carries Energy Energy transfers also happen when energy is carried by light. When light bounces off an object and into your eye, the object looks a certain way. Black construction paper looks dull but a mirror looks shiny. Some materials, like glass and water, you can see through. The differences in how these objects appear have to do with what happens when energy carried by light hits them. When light carries energy and transfers it to an object, three things can happen. One thing that can happen is that light reflects, or bounces off. All materials that you can see reflect some light. But materials that you cannot see, like air, do not reflect much light. A second thing that can happen is that the light passes through the materials. The energy carried by light passes through clear materials like air, glass, and water. A third thing that can happen when light hits material is that the material can absorb, or take in, the light. When a material absorbs the energy carried by light, the material heats up. For example, when you wear a black shirt on a sunny day, the shirt becomes hot. This happens because the energy transferred by light is absorbed by the material that makes up the shirt. The energy carried by light is absorbed by the shirt and changes into heat. © Teachers’ Curriculum Institute
Some energy is carried by light. When this energy is transferred to other objects, different things can happen. It can pass through materials that you can see through, like glass.
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Draw and label a diagram that shows how light can transfer energy to an object. Make sure these terms are used in your diagram: absorb, light, reflect, and transfer.
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4. Heat Carries Energy When energy is transferred as heat to other objects, it warms the objects up. Consider how you make toast. You put a piece of bread in a toaster and push the knob down. The wires in the slot of a toaster begin as gray and cool, but when they heat up, they start to glow with an orange light. What makes these objects glow when they get hot? Energy transferred as heat can produce light. You cannot always see it, but the material that makes up objects is always moving. Adding energy as heat to an object can cause its material to move faster. This makes its temperature rise, too. The more energy added to an object, the faster its material moves and the higher its temperature rises. If you add enough energy to an object, it makes more heat and light. For example, energy is added to the metal wires in a toaster. The material moves so fast that it gives off light and glows. As an object gives off light, it loses energy. But since energy is always conserved, this energy is not destroyed. The light carries the energy away from the object. In a toaster, the heat produces light. The energy carried by light transfers to the bread and heats it up. © Teachers’ Curriculum Institute
The wires in a toaster use heat to produce light and toast bread.
Metal can get so hot that it gives off light. Here, a horseshoe is being heated by a blacksmith. The horseshoe is glowing because energy transferred as heat is producing light.
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Draw and label a diagram that shows how heat carries energy. Make sure these terms are used in your diagram: heat, light, temperature, and transfer.
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5. Imagining Sound, Light, and Heat Without Conserved Energy Sound, light, and heat are different ways that energy can move from place to place. The energy they carry is always conserved. An object’s energy was not created from nothing. It came from the original source of the heat, light, or sound. When an object loses energy as heat, light, or sound, the energy is not destroyed. It is simply transferred to a new object. What would happen if energy were not conserved? Consider some impossible situations in which energy is not conserved. When you speak, vocal folds inside of you vibrate and transfer energy to the air, which vibrates and produces sound. The air then has the energy lost by the vocal cords. What if energy carried by sound was destroyed? Energy might not transfer to air. So, you could shout as loudly as you can, but you might not make a noise. Consider what would happen if the energy carried by light was not conserved. The light of a flashlight carries energy away from the bulb to other objects. You might hold a notebook in front of a flashlight. If more energy hit the paper than came out of the flashlight, the paper would burn from all the extra energy. This does not happen because energy is conserved even when it is carried away from a flashlight bulb. © Teachers’ Curriculum Institute
If energy was not conserved, a flashlight might burn a piece of paper when it shined. But this situation is impossible because all energy is conserved.
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You are trying to explain how sound, light, and heat conserve energy to a friend. Write a letter explaining what it would be like if sound, light, and heat did not conserve energy.
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Drop a pencil on your desk. Did you hear the sound it made? When the pencil was falling, it had energy of motion. Draw and label a simple diagram that shows how the energy was transferred to the desk and to the air around the desk. Include these terms in the labels of your diagram: collision, energy, sound, and transfer.
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CHECK
FOR
UNDERSTANDING
Show What You Know
Write a caption for this image describing how energy is transferred. Use these terms in your caption: energy, heat, light, sound, and transferred.
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CHECK
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UNDERSTANDING
Making Sense of the Phenomenon Let’s revisit the phenomenon: This car isn’t moving, but the woman’s hair is still blowing around. Think about: • What is causing her hair to move? • Besides movement, what are other ways that energy can be transferred?
Use your findings from the investigation to answer this question: How are you experiencing energy transfer right now? Claim
Evidence
Reasoning
Go back to page 4 and fill out the unit checkpoint for this lesson.
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Performance Assessment:
Creating a Safety Pamphlet Create a safety pamphlet for your school. Inform people about bike safety. You will: • describe the different ways that energy transfers between objects. • make a pamphlet with safety tips on how to protect yourself from motion energy.
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PERFORMANCE ASSESSMENT
Observing Energy Transfers Watch the video. What forms of energy can you observe in a bike race?
Now, observe the bike crash in this video. How does motion energy play a role in a bike collision?
How are other types of energy transferred from this collision? Fill in the table below.
Energy
Give an example of how this energy transfers from place to place.
Is it transferred during the collision?
If so, provide evidence.
Sound
Light
Heat
Electric Current
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PERFORMANCE ASSESSMENT
Consider how the bike collision would change if the bike was going at different speeds. Predict how the collision in the video might change if the bicycle was going half as fast.
Predict how the collision in the video might change if the bicycle was going twice as fast.
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PERFORMANCE ASSESSMENT
Understanding How a Bicycle Helmet Works Bicycle helmets help protect us from forces during a collision and change the way energy is transferred. They keep us safe if we crash our bikes. Why is it dangerous for all the energy to be transferred to your head at once?
How does a bike helmet change the way energy is transferred during a crash? How does that make you safer?
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PERFORMANCE ASSESSMENT
Planning Your Safety Pamphlets Based on your observations of energy in a bike collision, create a two-part safety pamphlet to explain how bicycle helmets protect you.
What is energy?
How does a bicycle helmet work?
The first part of your pamphlet should answer: What is energy? What are the different kinds and how can they be transferred? The second part of your pamphlet should answer: Why is wearing a helmet important during higher speed collisions? Use the observations, evidence, and explanations that you gathered in the previous steps to outline your safety pamphlets below.
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PERFORMANCE ASSESSMENT
Completing and Sharing Your Safety Pamphlets Look at your planning from the previous step. Use your planning to create your pamphlet. Is your pamphlet neat and colorful? Share your pamphlet with other students in the class.
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Lesson 5
How Is Energy Stored and Used?
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INVESTIGATION
Observing Phenomena Discuss: Have you ever seen solar panels on the roof of a building? What is the purpose of these solar panels?
Observe this phenomenon: A traffic light can be powered by the sun.
Find It!
Can you find other objects around you that are solar-powered? What about battery-powered objects?
Think of what you already know about solar panels and how they work. Write questions you have.
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INVESTIGATION
Defining the Problem Oh no! Someone has been in your brother’s lunchbox. Design a way to keep others out. Use what you’ve learned to design an alarm to warn your brother when the lunchbox is opened. You will act like engineers. Follow these steps. Remember, it is good to return to previous steps when needed!
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INVESTIGATION
Define the problem. What are the criteria for a successful lunchbox alarm? What are the constraints? Criteria:
Constraints:
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INVESTIGATION
Planning a Design Come up with a design for your lunchbox alarm. Draw and label a diagram of your design. Your labels should show how the design meets the criteria.
Write about any of the constraints that are a problem.
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INVESTIGATION
Building the Design Use your materials to build your alarm.
Testing the Design Turn on your alarms and close your lunchboxes. Pass your lunchbox to another group. Don’t show the other group your design or tell them how the alarm works. Now, try to open the lunchbox you received. Don’t set off the alarm! Make notes here. Then, regroup to share your findings with the team that designed the alarm.
What problems did the group testing your alarm find? How were they able to open the lunchbox without setting off the alarm?
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INVESTIGATION
Vocabulary Tell whether each sentence is describing something efficient. Write true or false. 1. Being useful without creating a lot of wasted energy. 2. Making many copies of one object. 3. Electricity that moves from a battery to an object.
My Science Concepts Reflect on your understanding. Draw an X along each line. Stored energy can be “used” to perform a variety of different tasks at different times or places from where the stored energy started. Examples of stored energy include food, gasoline, and batteries. still learning
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When energy is used, it is converted from one form where it is stored into another form, where it performs a useful function such as moving an object or making sound or light. still learning
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When people’s needs change, the engineering design process can be used to meet their demands. still learning
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1. Energy Is Stored A person can bring a music player anywhere by just putting it in his or her pocket. All he or she has to do is turn it on to hear a favorite song. This is because a music player has stored energy. There are many ways to store energy. The music player stores electric energy in its battery. This stored energy makes an electric current, which goes to a speaker to produce sound. Food you eat has stored energy. So does the gasoline that you put in a car. The energy in food and gasoline are stored and released when the food and gasoline break down. So, the stored energy in food becomes energy that you use to do things. The stored energy of gasoline becomes energy that the car uses to move. You might have heard somebody say, “We need to produce more energy.” You’ve learned that energy cannot be created. So, what does this expression mean? To produce energy means to change energy into a useful form. For example, dams store water so that they can produce an electric current whenever they need to. Dams hold back lots of water that has stored energy. When the water is released, it falls into a river and spins a turbine that produces an electric current. © Teachers’ Curriculum Institute
Stored energy can be used at a different time or place from where it started out. Batteries, gasoline, and dams are all objects that have stored energy. Lesson 5 How Is Energy Stored and Used?
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From your experience, you already know many objects that use energy. In the chart below, list at least one example of something that uses each source of stored energy. (Try to be as creative as possible and come up with examples that you have not learned in this lesson!) Source of Stored Energy
Example of an Object That Gets Energy from This Source
Battery
Food
Gasoline
Gravity
Electical outlet (connected to a power plant)
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2. Stored Energy Is Useful Energy cannot be created or destroyed. Yet, you might hear people say that the energy was “used up.” What do you think they mean? Stored energy can be used at a different time or place from where it started out. When someone says they are “using energy,” they are talking about releasing stored energy. When stored energy is released, it is transferred from one object to another object. This transfer can cause motion, sound, heat, light, or an electric current. When you exercise, you are changing food’s stored energy into energy of motion. When you use the energy in a battery, the energy is transferred to a wire, causing an electric current. That current can transfer energy to other objects.
You might need energy in between lunch and dinner. You can carry an apple in your bag. The stored energy of an apple is easier to carry around than a lot of other foods.
Stored Energy Can Be Useful in Different Times and Places
Some kinds of stored energy are useful because they can easily move to different places. You are not always near an electrical outlet, but you can easily bring batteries wherever you go. Batteries let you move energy to other objects in different places. Food and gasoline can also be moved to where they are needed. A car carries gas in its gas tank that stores the gas until the car needs it to move. You might carry a snack in your bag so that you can eat later when you are not near a kitchen. © Teachers’ Curriculum Institute
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Some Stored Energy Is Less Wasteful
Some kinds of stored energy are more efficient than others. To be efficient means to be useful without creating a lot of wasted energy. Consider a car that runs on energy stored in gasoline. When the car releases its energy, some of that energy heats the engine and the road. That heat does not help the car move. But now think about a car that runs on electricity stored in a battery. This car might release less heat than the other car, so less of its stored energy is wasted. More of its stored energy is used to move the car. In this case, the car that runs on electricity is more efficient, and the car that runs on gasoline is less efficient. Some Stored Energy Is Less Expensive
Some kinds of stored energy are useful because they do not cost very much to buy. These days, a car that runs on gasoline is often less expensive to buy than a car that runs on energy stored in batteries. As people invent ways to make cheaper car batteries, this might change. The same is true for buying and setting up solar cells. It is often more expensive to put solar cells on a home than to connect to a power plant using power lines. But once they are set up, solar panels can be much cheaper to use. 110
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A car that runs on energy stored in a battery is called an electric car. Electric cars can be more efficient than cars that run on gasoline.
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Conduct a short research project online to find out more details about electric cars today. Then use your research and the text to explain three advantages and three disadvantages of electric cars that use stored energy from batteries. List your sources. Advantages
Disadvantages
Sources:
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3. Engineers Use Energy to Solve Problems Suppose that rangers at a national park need a new ranger station. So, during the summer, the park hires an engineering company to design a plan for meeting the energy needs of the new station. The company assigns several engineers who, like most engineers, work as a team. Defining the Problem
The first step the team of engineers takes is defining the problem. The rangers who will use the new station have many needs. They need heat to cook food and light to be able to see at night. They also need radios to communicate with rangers at other stations. The best way to power all of these activities is with electricity. But the challenge is that there are no power lines near this part of the park. So, the engineers need to solve the problem of bringing power to the cabin. The engineers have several limitations for their design. The first limitation is that they cannot spend more money than the park can afford. The second is that the cabin must be built before the harsh winter weather comes. The third is that the rangers want to keep the land as natural as possible so that they do not harm nearby living things. The engineers can only make small changes to the land. What is the best way to get electricity to the new station? 112
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The new ranger station needs electricity. It also needs to be small so that it does not harm living things nearby. So, engineers must design a solution to this problem.
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Proposing Solutions
Each engineer on the team chooses a kind of energy resource to think about using at the new station. One person considers using the same energy source used at the old ranger station. That station uses electricity from a power line that came from a nearby city’s power plant. Another person thinks about ways to use gasoline and a small generator to produce an electric current. Other choices the team considers are solar cells and a wind turbine. There is a creek nearby, so someone also looks into a way to use water power. Choosing the Best Solution
The team meets to discuss the advantages and disadvantages of each energy source. Building power lines from the other station to the new station would change the land too much. So would building a large wind turbine or a dam on the creek. Burning gasoline in a generator would make too much noise and smoke. Solar cells are one of the most expensive choices to build. But they would meet all of the energy needs of the new station. They would also not take up too much space. They could be placed on the roof of the station. And, they would use the energy of sunlight, which is easy to come by in the park. So, the team decides that solar energy is the best way to power the station. © Teachers’ Curriculum Institute
Each kind of energy resource has pros and cons. The best solution for powering the new ranger station has to have pros that outweigh the cons. So, each engineer on the team has to think about the different resources they can use.
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This girl is riding a four-wheeler. Hopefully she is driving carefully! Suppose you are an engineer and you want to build your own fourwheeler. Which type of stored energy would you use to power your vehicle? Complete each engineering task below.
Define the problem. What are you trying to solve? What constraints (materials, time, cost) would you have?
Brainstorm solutions. Think about all the different types of stored energy that you’ve learned about that might be helpful.
Choose the best solution. Make an argument for why you think this is the best solution.
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4. Energy Can Solve Everyday Problems You and a friend are excited about the contest you are entering. To win, you must design and build a way to cook food without fire. Your limitations are that you cannot spend more than $30, and you only have six weeks to create your design. Like engineers, first you define the problem you are trying to solve. You know you need to cook food without using the stored energy of wood and other fuels. You also have cost and time limits. You decide to design a solar oven that will transfer energy from sunlight to food, heating it. Your friend goes to the library to find out how other people have made solar ovens. You go to the store to buy tools and materials. Together, you build a working solar oven so that you can test your design. Days before the contest, you test the oven. It is very sunny, so it works perfectly. But on the morning of the contest, you see a problem. It is cloudy, so there is not enough sunshine for the oven to work. Thinking quickly, you come up with a way to improve the oven. You add a battery-powered lamp to use on cloudy days. The lamp produces light and heat so that the oven can cook the food even when there is no sunlight. It uses stored energy instead of sunlight. Problem solved! © Teachers’ Curriculum Institute
When designing something, you define the problem, think of ways to solve the problem, and select a design. After, you build and test your design, like these students testing a solar oven. You see if it works and if it needs to be improved.
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Think of an everyday problem that you might be able to solve with energy. Draw a picture of the problem below. Then complete each task.
Define the problem. What are you trying to solve? What constraints (materials, time, cost) would you have?
Brainstorm solutions. Think about all the different types of stored energy that you’ve learned about that might be helpful.
Choose the best solution. Make an argument for why you think this is the best solution.
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Show What You Know Think of the different ways that energy is stored and used. Write captions for each image below that explain how the stored energy is converted to another form.
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Making Sense of the Phenomenon Let’s revisit the phenomenon: A traffic light can be powered by the sun. Think about: • If this traffic light wasn’t powered by the sun, how else might it get energy? • What is the benefit of stored energy sources that are efficient? Use your findings from the investigation to answer this question: What problems are the solar panels solving? Claim
Evidence
Reasoning
Go back to page 4 and fill out the unit checkpoint for this lesson.
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Grade 4 TCI’s Grade 4 program includes four units. Each unit has a Science Journal, complete with hands-on investigations, text with notes, and checks for understanding.
Unit 2
Unit 1 Plant and Animal Structures 1 What Plant Structures Are Used for Support and Growth?
6 What Animal Structures Are Used for Support, Movement, and Protection?
2 What Plant Structures Are Used for Protection?
7 What Animal Structures Are Used for Reproduction?
3 What Plant Structures Are Used for Reproduction?
8 What Animal Structures Are Used for Sensing the
4 How Do Plants Respond to Their Environment? 5 What Animal Structures Are Used for Digestion and Circulation?
Grade 4
Energy Science Journal
Environment? 9 How Do Animals Respond to Their Environment? Performance Assessment: Designing a Legendary Creature
Unit 2 Energy 1 How Are Energy and Motion Related? 2 How Is Energy Transferred by Colliding Objects?
Performance Assessment: Creating a Safety Pamphlet
3 How Is Energy Transferred by Sound, Light, and Heat?
5 How Is Energy Stored and Used?
4 How Is Energy Transferred by Electric Currents?
6 How Do People Choose Energy Resources?
Performance Assessment: Designing a Safety Device
Unit 3 Earth’s Changing Surface 1 What Are Some Clues That Earth’s Surface Changes? 2 How Does Water Change Earth’s Surface? 3 How Does Wind Change Earth’s Surface?
Performance Assessment: Investigating Changes to the Appalachian Mountains 6 Where on Earth Are Earthquakes, Volcanoes, and Mountains Found?
4 How Do Living Things Change Earth’s Surface?
7 What Can People Do About Natural Hazards?
5 How Do Fossils Form and What Do They Show?
Performance Assessment: Developing Hazard Plans
Unit 4 Waves and Information 1 What Are Some Examples of Waves?
5 How Can Sound Waves Be Used to Send Messages?
2 What Are Some Properties of Waves?
6 How Can Patterns Be Used to Send Messages?
3 How Do Waves Affect Objects?
Performance Assessment: Developing a
4 Which Waves Travel Through Earth?
Communication Method Using Waves
Engineering
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