Energy Transfers Do Now Questions: Look at this picture of a fairground. Identify as many different energy stores and transfers as you can. Challenge: List three energy transfers that are useful and three that are not useful. Key Words: Energy transfers Wasted Useful Dissipated Lesson Objectives: • Represent energy transfers using diagrams and describe what happens to wasted energy in energy transfers • Interpret diagrams that represent energy transfers and explain, using examples, that energy is conserved Big Question: What is energy? Tuesday, 28 September 2021 Possible stores: Possible transfers: kinetic: the moving roller coaster and chair ride, dodgem cars, bullets in rifle range, etc. by light and sound: any lights in the fairground, any music from rides, screams from roller coaster riders etc. gravitational potential: roller coaster cars, chair ride (especially the chairs at the top), hammer above girl’s head by heating: from bodies, from the cooker in the fish and chip stall chemical: candy floss, fish and chips thermal: human bodies, cookers in fish and chip stall by forces: moving the chair ride around, starting the roller coaster off, dodgem cars hitting each other by electricity: supply to motors in the rides, to lights Possible useful energy transfers: • kinetic to gravitational potential and back as the roller coaster moves along the ride • by heating from cooker in fish and chip stall to food • by electricity to motors in dodgem cars Possible wasted energies: • energy released by heating from motors etc. • by sound from noise of roller coaster moving • by heating from cooker in fish and chip stall to the surroundings What energy stores and transfers can you identify from these images? Energy Transfers Energy is being transferred: - to the kettle by electricity - to the water in the kettle by heating - to the kettle and the surroundings by heating Energy is stored in: the hot water, kettle and surroundings as thermal energy. Lesson Objectives: • Represent energy transfers using diagrams and describe what happens to wasted energy in energy transfers • Interpret diagrams that represent energy transfers and explain, using examples, that energy is conserved Big Question: What is energy? Energy Transfers Energy is stored in the stretched rubber as elastic potential energy. When the stone is released, energy will be transferred to the stone by a force from the rubber band. Energy will be stored in the moving stone by kinetic energy. Lesson Objectives: • Represent energy transfers using diagrams and describe what happens to wasted energy in energy transfers • Interpret diagrams that represent energy transfers and explain, using examples, that energy is conserved Big Question: What is energy? Energy Transfers Energy is stored in the fuel as chemical energy. Energy is transferred to the air inside the balloon by heating. The balloon is above the ground, so it is storing gravitational potential energy. The energy was transferred to the balloon by an upthrust force. Lesson Objectives: • Represent energy transfers using diagrams and describe what happens to wasted energy in energy transfers • Interpret diagrams that represent energy transfers and explain, using examples, that energy is conserved Big Question: What is energy? Energy Transfers Energy is transferred to the lights and sound system by electricity. Energy is transferred to the people by light and sound. Energy is also transferred from the lights by heating. The energy is stored in the people and surroundings as thermal energy. Lesson Objectives: • Represent energy transfers using diagrams and describe what happens to wasted energy in energy transfers • Interpret diagrams that represent energy transfers and explain, using examples, that energy is conserved Big Question: What is energy? What words should appear in the gaps? List them on a whiteboard: Energy is stored in our bodies. Energy stored in this chemical way is sometimes called 1___________ energy. As you climb up to a diving board, some of the energy gravitational stored in your body is transferred to 2___________ potential energy. When you jump from a diving board, potential the gravitational 3___________ energy is transferred to kinetic 4__________ energy as you accelerate downwards. Not all the energy is transferred as useful energy – your thermal body gets warmer as you climb, and this 5__________ energy is transferred to your surroundings by heating 6___________. by heating by light by sound chemical gravitational kinetic potential thermal elastic Mini Plenary Complete an interconnectivity web for the energy stores. Use this to identify a device or method of transferring energy from one store to another. Ext. Can you pair every store? Guitar Explain energy transfers involved in changing motion, dropping an object, completing an electrical circuit, stretching a spring, metabolism of food, and burning fuels Where does the energy go? Explain energy transfers involved in changing motion, dropping an object, completing an electrical circuit, stretching a spring, metabolism of food, and burning fuels Where does the energy go? Explain energy transfers involved in changing motion, dropping an object, completing an electrical circuit, stretching a spring, metabolism of food, and burning fuels Where does the energy go? Explain energy transfers involved in changing motion, dropping an object, completing an electrical circuit, stretching a spring, metabolism of food, and burning fuels Where does the energy go? Explain energy transfers involved in changing motion, dropping an object, completing an electrical circuit, stretching a spring, metabolism of food, and burning fuels Where does the energy go? Explain energy transfers involved in changing motion, dropping an object, completing an electrical circuit, stretching a spring, metabolism of food, and burning fuels Where does the energy go? Law of Conservation of Energy ‘Energy can not be created or destroyed, it can only be transferred from one store to another.’ However, energy is not always transferred into stores that are useful, it is dissipated (spreads out) so that it is stored in less useful ways. Lesson Objectives: • Represent energy transfers using diagrams and describe what happens to wasted energy in energy transfers • Interpret diagrams that represent energy transfers and explain, using examples, that energy is conserved Big Question: What is energy? Why does the ball lose height as it bounces? �Some of the energy stored as GPE is transferred to the surroundings by heating and sound with each bounce. We can represent useful and wasted energy as Sankey Diagram… Sankey diagram clues • Uses arrows to show useful and wasted energy • Useful energy transferred points upwards, wasted energy transferred points downwards • Width of the arrow represents the amount of energy transferred • The energy out (J) must be equal to the energy in (J) 🡪 Use the clues to sketch a Sankey for a light bulb where energy is transferred by electricity into 5J of energy transferred by light and 7J of energy transferred by heating. Lesson Objectives: • Represent energy transfers using diagrams and describe what happens to wasted energy in energy transfers • Interpret diagrams that represent energy transfers and explain, using examples, that energy is conserved Big Question: What is energy? Light Bulb: Now Sketch a Sankey diagram for a kettle using these values: • 1000J of energy is transferred to a kettle • 850J ends up stored in the hot water Challenge: Draw a Sankey diagram for a television. Master Learning List 1. Write down 3 facts that you have learnt today. 2. Share you facts with your team and make a master list of the most common fact learnt to the least common. 3. Did other groups have the same most common fact? Plenary National Curriculum ∙ Draw an interconnectivity web for the energy stores ∙ Explain energy transfers involved in changing motion, dropping an object, completing an electrical circuit, stretching a spring, metabolism of food, and burning fuels ∙ Describe how the amount of energy transferred can be changed.
