IGCSE›Oxford AQA IGCSE Physics›Mind mapsEnergy Transfers & Particle MotionOxford AQA IGCSE Physics: Mind mapStudy pack PDFAlso for this subtopic:Revision notesFlashcardsSubtopic testCover factsConductionEnergy passed on by particle collisionsParticles do not move from place to placeFree electrons make metals good conductorsInsulators lack free electrons, so transfer is slowConvectionHappens in fluids onlyHeated particles spread out, become less denseWarm fluid rises, cool fluid sinksForms a convection currentEvaporationMost energetic particles escape the surfaceHappens at any temperatureCondensation: gas particles lose energy and form a liquidBoiling happens throughout the liquid, at a fixed temperatureEnergy transferparticle motionFaster evaporationHigher temperatureLarger surface areaAir movement over the surfaceLower humidityRate of transferLarger surface area to volume ratio speeds transferGood conductors transfer faster than insulatorsDark matt surfaces radiate faster than shiny onesBigger temperature difference means faster transferCooling fins increase surface areaExam tipsAlways mention free electrons for metalsEvaporation is not only at boiling point