During this CELL, students will conduct several investigations focused on promoting an understanding of different types and forms of energy. By conducting experiments, investigating different variables, and examining energy conversions, students will begin to draw conclusions concerning the relationship between the potential and kinetic energy and the Law of Conservation of Energy.

Students will also discover that all forms of energy ultimately are converted to mechanical energy in order for systems and objects to do work. Students will explore the concept of energy conversion and conservation in a number of different ways in this CELL. They will begin their exploration of energy by discovering how the total energy of an object is the sum of its potential and kinetic energy. Through experiments with marbles of different masses and planes of different heights, students will learn that the energy of an object is influenced by its mass and that the potential energy of an object can be changed by changing its position. Through modeling and experimentation, students will explore how sound energy is generated and transmitted through different states of matter. Students will discover that sound travels in waves and that the characteristics of a sound wave determine its properties of pitch and volume. Students will explore electrical energy and light energy through experiments with circuits. Students will then examine energy conversion and the Law of Conservation of Energy as they apply to chemical energy and heat by observing and conducting experiments with endothermic and exothermic reactions. Students will then explore how mechanical energy can be generated from potential energy, kinetic energy, and chemical energy through experiments with model cars.

In the Performance Assessment, students will have an opportunity to apply their knowledge from this CELL, by selecting the appropriate materials needed to construct and test a method of converting sound to mechanical energy, and a method of converting chemical to heat energy. By the conclusion of this CELL, students should realize that the relationship between potential and kinetic energy can be understood and explained by way of reference to the Law of Conservation of Energy.

Through performing experiments and participating in class discussions, students will begin to comprehend that energy can be found in different forms and types throughout nature and the universe. Students will begin to understand that the Law of Conservation of Energy applies to all forms and types of energy and that the total energy of an object or system is the sum of its potential and kinetic energies. This CELL will promote students’ awareness of forms of energy that they encounter in their daily lives, building continuity between classroom investigations and daily applications.

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Investigation 1: Potential and Kinetic Energy

Investigation One introduces students to the relationship between potential and kinetic energy in the context of mechanical energy and investigates the effect of mass on potential and kinetic energy. Students will conduct a series of experiments to determine the effect of mass on the potential and kinetic energy of plastic and steel marbles by rolling each marble down an inclined plane into a plastic flower pot. Students will learn that the marble with the greater mass performs more work on the flower pot because it makes the flower pot slide further across the table. Students will discover through their experiments that the kinetic energy of an object increases as its potential energy decreases and that an object’s mechanical energy is the sum of its potential and kinetic energies.

Investigation 1: Teacher’s Video (7:38)

 Investigation 1: Student’s Video (11:36)

Click on the image below to open Investigation 1 CAP

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Investigation 2: Energy of Sound

In Investigation Two, students will explore how sound energy is produced by vibrations, and will study the nature of sound waves. Students will explore the transfer of sound energy through gas, water, and solids by exploring how an activated tuning fork can generate mechanical energy through air, water, and a ping-pong ball. In addition, students will explore the nature of wave behavior by investigating amplitude and pitch, two properties that are unique to sound energy. Students will discover that as the amplitude of a sound wave increases, the volume of the sound increases. Students will also discover that increasing the frequency of a sound wave will increase its pitch.

Investigation 2: Teacher’s Video Introduction (9:38)

Investigation 2: Teacher’s Video Stations (10:25)

Investigation 2: Student’s Video (11:05)

Click on the image below to open Investigation 2 CAP

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Investigation 3: Electricity and Energy      

During Investigation Three, students will examine another form of kinetic energy: electricity. Students will create circuits to explore how chemical potential energy can be converted to electrical kinetic energy, and that electrical kinetic energy is transformed into light energy and heat in a light bulb. Students will then compare their circuits to that of a flashlight, and discover that while circuits do not require wires to function, they must contain an energy source and some form of conductor for electrons to flow.

Investigation 3: Teacher’s Video (5:55)

Investigation 3: Student’s Video (9:47)

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Investigation 4: Chemical Energy and Heat

Investigation Four gives students an opportunity to further explore the concept of chemical energy. Investigation Three introduced students to the conversion of stored chemical energy into electrical energy by the completion of a circuit. This investigation demonstrates to students that electrical reactions also result in energy transfers. Students observe the process of sugar caramelization as an example of an endothermic reaction, which is a reaction in which heat is absorbed by the reactants. Students will then dissolve powdered non-chlorine bleach in water and observe the difference in the water temperature before and after the addition of bleach. Students will discover that this reaction is exothermic through their observation of the increase in temperature of the water.

Investigation 4: Teacher’s Video (5:51)

 Investigation 4: Student’s Video (7:41)

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Investigation 5: Energy and Motion

In Investigation Five, students will have an opportunity to investigate mechanical energy. Students will compare the effect of gravitational potential energy with the effect of the addition of the kinetic energy of moving air on the distance which a model car can travel. Students will then have the opportunity to explore how chemical energy can be transformed into mechanical energy as they use a reaction of baking soda and vinegar to generate a burst of carbon dioxide gas strong enough to remove a rubber stopper from the reaction vessel. Students will discover that the kinetic energy of the gas is converted into mechanical energy which is capable of propelling a model car when the reaction vessel is attached to the car.

Investigation 5: Teacher’s Video (7:46)

 

 Investigation 5: Student’s Video (11:13)

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Investigation 6: Performance Assessment

Investigation Six consists of a performance assessment designed to evaluate students’ understanding of the science concepts addressed in the first five Investigations of the CELL. During this exploration, students will use the knowledge they have gained about potential and kinetic energy, energy conversion, and five forms of energy: mechanical, heat, electricity, sound, and chemical.

Investigation 6: Performance Assessment – Teachers Only (5:46)