FOUNDATIONS OF PHYSICS Notebook Assignment #10 Energy Notes Energy Classified As Potential Energy Kinetic Energy Dissipated Energy Divided Into Gravitational Potential Energy Elastic Potential Energy ENERGY The ability to cause change Can be transferred from one place or object to another Can be converted from potential to kinetic or kinetic to potential Energy can not be created or destroyed. This is called the Law of Conservation of Energy. POTENTIAL ENERGY Stored Energy Has the potential to cause something to change, but is not currently causing a change Several different representations of potential energy. The two main categories: Gravitation and Elastic Potential Energy GRAVITATIONAL POTENTIAL ENERGY (GPE) Results from an object being raised up while the force of gravity acts on it. Depends on the force of gravity and how high the object is raised. ELASTIC POTENTIAL ENERGY (EPE) Results from an elastic material being stretched or compressed some distance. Depends on how far the elastic material is stretched / compressed and the material’s spring constant. OTHER EXAMPLES OF POTENTIAL ENERGY Chemical Potential Energy – Energy stored in the chemical bonds of substances like food, oil, natural gas, etc. Electrical Potential Energy – Energy stored in an object with voltage KINETIC ENERGY Energy of motion Depends on the speed of the object and its mass DISSIPATED ENERGY Energy that is converted into energy that can no longer be “used” as kinetic or potential energy. Dissipated energy usually remain in the original location or object or moves out into the surrounding environment ENERGY PIE CHARTS Used to illustrate conservation of energy and energy conversion The size of the pie (circle) indicates the total energy of the object(s) The size of the pie pieces (divisions in circle) illustrates the amount of each energy. Gravitational Potential Energy (GPE) Elastic Potential Energy (EPE) Total Energy Kinetic Energy (KE) ENERGY PIE CHARTS - WORKSHEET 1. A wind-up toy is fully wound and at rest. EPE All of the energy in the rabbit is stored in the “wound” spring ENERGY PIE CHARTS - WORKSHEET 2. A wind-up toy is wound up and moving across level ground. The toy is speeding up. KE EPE EPE KE Elastic Potential Energy is converted to Kinetic Energy EPE KE ENERGY PIE CHARTS - WORKSHEET 3. The toy is wound up and is moving at a constant speed up an incline. EPE KE GPE EPE KE GPE KE EPE Elastic Potential Energy is converted to Gravitational Potential Energy while Kinetic Energy remains constant ENERGY PIE CHARTS - WORKSHEET 4. The toy is wound up and moving along at a constant speed. KE EPE EPE KE Diss EPE KE Diss Elastic Potential Energy is converted to Dissipated Energy while Kinetic Energy remains constant ENERGY PIE CHARTS - WORKSHEET 5. The toy is wound up and slowing down as it moves up an incline. EPE KE GPE EPE KE GPE EPE KE Elastic Potential Energy is converted to Gravitational Energy while Kinetic Energy decreases ENERGY PIE CHARTS - WORKSHEET 6. The toy is wound up and speeding up as it moves up an incline. EPE GPE EPE GPE KE EPE KE KE Elastic Potential Energy is converted to Kinetic Energy and Gravitational Potential Energy