Heat TransferHeat Transfer

ConductionConductionConvection Convection RadiationRadiation

ConConduductctionion

ConductionConduction

Energy is transferred from Energy is transferred from molecule to molecule as they molecule to molecule as they collidecollideSolids are best at transferring Solids are best at transferring heat by conductionheat by conductionHeat is moves from Heat is moves from hothot to to coldcold

 

                            

Fast (hot) atoms Fast (hot) atoms bump into slow (cold) bump into slow (cold) atomsatomsFast atoms make Fast atoms make slower atoms speed slower atoms speed upupKinetic energy Kinetic energy (energy of motion) is (energy of motion) is transferred from hot transferred from hot to coldto coldTemperature is a Temperature is a measure of average measure of average kinetic energykinetic energy

ConvectionConvection

Transfer of heat energy by Transfer of heat energy by movement in fluids (liquids and movement in fluids (liquids and gases)gases)Warmer region of fluid expands Warmer region of fluid expands and becomes less denseand becomes less dense

ConvectionConvection

Less dense , Less dense , warmerwarmer material material rises, more rises, more dense, dense, coolercooler material sinksmaterial sinksConvection Convection currents formcurrents form

RadiationRadiation

Transfer of Transfer of electromagnetic energyelectromagnetic energy through space through space Electromagnetic energyElectromagnetic energy is energy in is energy in lightlightLight travels through space as a waveLight travels through space as a wave

Forms of Electromagnetic EnergyForms of Electromagnetic Energy

Radio wavesRadio wavesMicrowavesMicrowavesInfrared (heat)Infrared (heat)Visible lightVisible lightUVUVX-raysX-raysGamma raysGamma rays

Characteristics of electromagnetic Characteristics of electromagnetic radiationradiation

Travels through space at 186,000 Travels through space at 186,000 miles per secondmiles per secondEach form has a different Each form has a different wavelength, frequency and energywavelength, frequency and energyHigher frequency has more energyHigher frequency has more energy