P1.1.4 Conduction P1.1.5 Convection 3.5 / 5 based on 2 ratings ? PhysicsEnergy transfer by heatingGCSEAQA Created by: MaddiCreated on: 19-04-14 13:17 What is convection? Convection is the circulation of a fluid (liquid or gas) caused by heating it. 1 of 14 Where can convection take place? Convection takes place only in liquids and gases. 2 of 14 Why does convection occur? Heating a liquid or a gas makes it less dense so it rises and causes circulation. 3 of 14 Why doesn't conduction occur in solids? Conduction does not occur in solids because the particles are held in fixed positions and not able to flow. 4 of 14 Give an example of convection. Convection is responsible for onshore and offshore breezes. 5 of 14 What is conduction? Transfer of energy from particle to particle in matter. 6 of 14 What materials make the best conductors? Metals are the best conductors of energy. 7 of 14 What materials make the best insulators? Materials such as wool and fiberglass make the best insulators. 8 of 14 Why are metals good conductors? Conduction of energy in a metal is due mainly to free electrons transferring energy inside the metal. 9 of 14 Why are non metals poor conductors? Non-metals are poor conductors because they do not contain free elctrons. 10 of 14 Stages of conduction. (non-metals) Particles gain kinetic energy + vibrate more --> energy is passed to neighbouring particles --> energy is transferred through the solid 11 of 14 Stages of conduction. (metals) Free electrons gain kinetic energy + move through metal --> they transfer energy by colliding with other particles --> energy is transferred 12 of 14 Stages of convection. Fluid heated --> fluid expands --> fluid becomes less dense --> fluid rises --> warm fluid replaced by cooler, denser fluid --> convection current formed 13 of 14 Stages of convection. (immersion heater) Water particles gain energy + move faster --> particles move apart --> water becomes less dense --> hot water rises through tank 14 of 14
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