What type of heat transfer (conduction, convection, or radiation) causes each of the following?

a) Your face warms as you stand next to the fire.


b) The wind starts to blow and your face begins to cool.


c) Five minutes after a pot of water is placed on the fire, the top of the water begins to warm.


d) Your tongue is burned when you sip your hot chocolate.|||I'll start off with simple definitions.





Conduction - Transfer of heat via direct contact between two objects, bodies, materials, etc.





Convection - Transfer of heat via bulk movement. In other words, heat is transferred by motion of gases or fluids.





Radiation - Transfer of heat via emission of electromagnetic waves.





Now to answer each of the following with a brief explanation of why.





a) This is an example of radiative transfer because the fire is emitting electromagnetic waves.





b) This is an example of radiative heat transfer because the motion of air removes heat from your face. Not only that, but it helps evaporate sweat, thus allowing the latent heat of evaporation.





c) This is another example of convective heat transfer because the heat moves through the water towards the top.





d) This is an example of conductive heat transfer because the heat is able to move directly from the hot chocolate to the person's tongue. |||(a) Radiation


(b)Conduction


(c) Convection


(d) conduction