Energy Chains Grade Seven

Transcription

1 Ohio Standards Connection: Physical Science Benchmark D Describe that energy takes many forms, some forms represent kinetic energy and some forms represent potential energy; and during energy transformations the total amount of energy remains constant. Indicator 5 Trace energy transformation in a simple closed system (e.g., a flashlight). Scientific Inquiry Benchmark A Explain that there are differing sets of procedures for guiding scientific investigations and procedures are determined by the nature of the investigation, safety considerations and appropriate tools. Indicator 4 Choose the appropriate tools and instruments and use relevant safety procedures to complete scientific investigations. Lesson Summary: In this lesson, students learn about energy transformations and will be able to trace them in a simple closed system. Students will build energy chains, of their own design. Students will complete a hands-on project where they will attach the links in a "chain" connecting a battery (chemical energy), wires (electrical energy), and a small motor (mechanical energy), and then add additional links of their choice. Students will complete a flowchart tracing the energy transformations in the finished project. The Pre- Assessment will measure their knowledge of energy forms and comprehension of energy transformations in familiar appliances. In the Post-Assessment, students will trace energy transformations in a variety of electronic devices. Estimated Duration: Two hours Commentary: In a closed system, energy is neither gained nor lost, and may be transformed between potential and kinetic forms. Most energy devices require this transformation in order for them to work, and often the goal of technological design is discovering new energy transformations. This lesson challenges students to design and build circuits that have the greatest number of energy transformations. Designing models of these circuits helps students understand the nature of these transformations, and building the circuits aids in retention of the concepts. Pre-Assessment: Have students complete the exercise in Attachment A, Pre- Assessment. Scoring Guideline: See Attachment B, Pre-Assessment Answers, for a list of possible student answers. 1

2 Post-Assessment: See Attachment C, Post-Assessment, for a handout that students are to complete. Scoring Guideline: See Attachment D, Post-Assessment Answers, for a list of appropriate responses for the Post- Assessment. Instructional Procedures: 1. Following the pre-assessment, promote classroom discussion about energy forms, providing examples from the Scoring Guide or the students Pre-Assessments. Help students understand that there are many ways that a person can encounter energy in different forms. Instructional Tip: You should discuss devices and appliances that work because of multiple energy transformations with the energy forms in different arrangements. It may be helpful to have several battery-operated devices available (e.g., a flashlight or CD player) to help delineate the transformations and provide a lead-in to the construction project. 2. Challenge student teams to design and build a device that has multiple energy transformations. Hand out Attachment E, Energy Chains Activity and help students understand the directions. Each student team will be responsible for handing in one worksheet. Directions on the worksheet follow in the instructional procedures printed below. 3. Students will begin by attaching a battery (chemical energy) to wires (electrical energy). 4. Next, have students attach wires to a small electric motor (mechanical energy). 5. Have teams prepare drawings on separate sheets of paper showing the energy transformations in the circuits they have built. On the drawing, students should indicate the form of energy that each part represents. 6. Have students design a larger circuit using add-on components that are available in the classroom, maximizing the number of energy transformations that are made. Instruct students to draw these on their diagrams, and to label all forms that energy takes as it travels through their circuit. Instructional Tip: It may be necessary to explain energy bridging or using the motor to close the circuit to another battery, which in turn is attached to additional devices which provide energy transformations. 7. On a separate piece of paper, have students draw flow charts that show the flow of energy through their systems. 2

3 8. Review and approve all plans before students attempt to construct them. You should consider safety concerns (especially short-circuits and the use of thermal energy), and whether the energy chain will work properly. 9. Have teams build their proposed projects. 10. Have student teams demonstrate their invention to the class and trace the energy transformations. 11. Request team members to identify problems they experienced while building their energy chain project, adjustments they would make if they build a similar project, or advice they would give to other teams to complete this type of project in the future. Differentiated Instructional Support: Instruction is differentiated according to learner needs to help all learners either meet the intent of the specified indicator(s) or, if the indicator is already met, to advance beyond the specified indicator(s). For any student who finds the general directions difficult to follow or needs additional guidance with the construction phase of the project, a set of simple steps for creating an Energy Chain are found in Attachment F, Alternative Instructions. Depending on available resources, supplies and equipment, there are a large number of chains that could be developed using these steps. Extensions: Have students take apart a broken or discarded battery operated toy or simple appliance and trace the components that transfer energy. Have students create a mobile showing the transfer of energy in a device or appliance. Have students look through catalogs or magazines to find examples of energy forms. Pictures could be cut out and included with a description of each energy form as a guide to other students, or a collage could be created and used to exemplify each energy form. Homework Options and Home Connections: Have students prepare a list of items in the home which depend on a transfer of energy for proper operation and trace the transfer of energy. Parents, siblings and relatives can be involved when students explain the energy transformations in a common appliance and give family members a quiz to test their understanding. The success of this teaching experience can then be shared with classmates. Interdisciplinary Connections: English Language Arts Research Benchmark C: Organize information in a systemic way. Indicator 4: Select an appropriate structure for organizing information in a systematic way (e.g., notes, outlines, charts, tables and graphic organizers). 3

4 Materials and Resources: The inclusion of a specific resource in any lesson formulated by the Ohio Department of Education should not be interpreted as an endorsement of that particular resource, or any of its contents, by the Ohio Department of Education. The Ohio Department of Education does not endorse any particular resource. The Web addresses listed are for a given site s main page, therefore, it may be necessary to search within that site to find the specific information required for a given lesson. Please note that information published on the Internet changes over time, therefore the links provided may no longer contain the specific information related to a given lesson. Teachers are advised to preview all sites before using them with students. For the teacher: Copies of attachments. For the student: Batteries (D-dry cell), battery clips, battery holders, #10 insulated bell wire, electric motor, solar cell (use outdoors or w/incandescent light), bulb holder, 2-volt miniature light bulb, wire stripper/cutter, screwdriver, electric bell, construction materials such as wood, pipe cleaners and paper. Vocabulary: acoustic energy chemical energy electrical energy energy energy transformations mechanical energy nuclear energy radiant energy thermal energy Technology Connections: Have students brainstorm a list of new inventions or improvements to appliances and then attempt to list all of the energy transformations needed to make them work. Research Connections: Marzano, R. et al. Classroom Instruction that Works: Research-Based Strategies for Increasing Student Achievement. Alexandria: Association for Supervision and Curriculum Development, Nonlinguistic representations help students think about and recall knowledge. This includes the following: Creating graphic representations (organizers); Making physical models; Generating mental pictures; Drawing pictures and pictographs; Engaging in kinesthetic activity. 4

5 Cooperative learning groups have a powerful effect on student learning. This type of grouping includes the following elements: Positive interdependence; Face-to-face promotive interaction; Individual and group accountability; Interpersonal and small group skills; Group processing. Setting objectives and providing feedback establishes a direction for learning and a way to monitor progress. This provides focus on learning targets and specific information to allow the student to make needed adjustments during the learning process, resulting in the increase of student learning. General Tips: Only a small selection of possible answers has been provided for the Pre-Assessment. If there is a question about the responses given, allow students the opportunity to explain their ideas and defend their understanding of energy forms and/or energy transformations. Possibly their responses are a unique way of defining a very complicated concept. The energy forms listed in this lesson may have different names than those used in older science texts. Radiant energy also has been described as light energy and heat energy. Acoustic energy used to be called sound energy. Magnetic energy is absent from the contemporary list, but is included under the listing of electrical energy. Although the words light, heat and sound are more familiar to most students, an effort should be made to use the new terminology and explain how these terms allow for a broader understanding of each energy form (i.e., radiant energy could include the entire electromagnetic spectrum, not just visible light and heat). Students should be encouraged to attempt creative or elaborate energy chains even at the expense of time and materials. Energy chains are the framework of invention. Even if they don t work, they can become a springboard to discussion, problem-solving, and inspiration. It is important to note that the concept energy transformations will be revisited throughout the science curriculum (e.g., energy pyramid, energy convection under the Earth s crust, and the energy exchange on a roller coaster ride ). Attachments: Attachment A, Pre-Assessment Attachment B, Pre-Assessment Answers Attachment C, Post-Assessment Attachment D, Post-Assessment Answers Attachment E, Energy Chains Activity Attachment F, Alternative Instruction 5

6 Attachment A Pre-Assessment For each of the following energy forms, provide two examples: Energy Form Example #1 Example #2 1. Electrical 2. Mechanical 3. Chemical 4. Thermal 5. Radiant 6. Nuclear 7. Acoustic The Principle of the Transformation of Energy states that any form of energy can be changed to any other form of energy. Identify a device which uses each of the following transformations: Energy Transformation Device 1. Electrical to Radiant 2. Chemical to Thermal 3. Electrical to Mechanical 4. Radiant to Thermal 5. Mechanical to Acoustic 6

7 Attachment B Pre-Assessment Answers The following are examples of likely responses. Students may give responses that are associated with a particular energy form (e.g., writing wires for an example of electrical energy), or they may provide an application of that energy form (e.g., writing TV for an example of electrical energy). If there is not a direct connection, then they should be asked to clarify their responses. For the purpose of scoring this Pre-Assessment and to indicate a general understanding of each energy form, both examples should be directly associated with that form or an application of that energy form. To indicate an understanding of the Principle of Transformation, students should correctly identify four out of five devices. Energy Form Example #1 Example #2 1. Electrical Electric Circuit Lightning 2. Mechanical Motor Generator 3. Chemical Gasoline Firecracker 4. Thermal Furnace Campfire 5. Radiant Light bulb Light stick 6. Nuclear Power plant Atomic bomb 7. Acoustic Bell Voice Energy Transformation Device 1. Electrical to Radiant Electric light bulb, television, video games 2. Chemical to Thermal Candle burning, gas water heater 3. Electrical to Mechanical Electric motor, washing machine 4. Radiant to Thermal Solar water heater, light bulb 5. Mechanical to Acoustic Piano, lawn mower 7

8 Attachment C Post-Assessment 8

9 Attachment D Post-Assessment Answers 9

10 Attachment E Energy Chains Activity Energy Chains Materials: 2 batteries (D) 4 battery clips 2 battery holders 2ft #10 insulated bell wire 1 electric motor 1 solar cell (use incandescent light) 1 bulb holder 1 electric bell 1 wire stripper/cutter 1 screw driver 1 2-volt miniature light bulb Paper, glue, scissors, foil, cardboard, pipe cleaners Directions: Your team will be designing and constructing a device that uses a sequence or chain of energy transformations to work properly. Part of this energy chain has been designed for you, and part of the project will be invented by your team. Your team also will trace the energy transformations throughout the device. After all projects are completed, your team will demonstrate your invention to the class, explain how it works, and list the energy transformations. Begin by connecting two battery clips to a battery in a holder, and then run wires from the battery clips to the connections on the electric motor. When complete, the motor should run. Do not leave the wires connected to the motor very long or you ll run down the battery. Your team s device has taken the chemical energy in the battery, transformed it to electric energy in the wires, and finally to mechanical energy in the motor. Your team challenge is to take the mechanical energy in the motor and transform it to radiant energy, acoustic energy or thermal energy using only the materials provided. It may be necessary to construct an energy bridge to complete this project. An energy bridge uses the electric motor to turn on or off a separate energy chain that accomplishes the challenge. Before continuing this project, follow these steps: 1. Draw a diagram of the battery, wires and electric motor. 2. On the diagram, label the form of energy each part represents. 3. On the diagram, add the materials/equipment you ll need to complete the project. 4. Label all forms of energy included in the new plans. 5. Trace the entire list of energy transformations using a flow chart. 6. Have all plans approved by the teacher before construction. Draw the diagram on a separate piece of paper. 10

11 Attachment F Alternative Instructions 1. Place a battery in the battery holder with clips. 2. Place the tip of one wire in one battery clip, place another wire in the other clip. 3. Hook the other end of one of the battery wires to one motor clip, hook the other wire to the other motor clip. 4. If the motor is working, pull one wire loose to stop the motor. If the motor doesn t work or the wires become hot, quickly ask for the teacher s help. 5. Place another battery in a battery holder with clips. 6. Place the tip of a new wire in one battery clip, place another new wire in the other clip. 7. Hook the other end of a new battery wire to one light socket clip, hook the other new battery wire to the other socket clip. 8. Place a light bulb in the socket. 9. If the light is working, pull one of the wires loose to turn the light out. If the light doesn t work or wires become hot, quickly ask for the teacher s help. 10. Using the other supplies, think of a way the turning motor could move or pull something to turn on the light. 11. Try your idea. Remember you will have to hook back the wires that you unattached from the motor and light bulb. 12. If it works, try to think of other energy chains you can build. If it doesn t work, ask for the teacher s help. 11