Conduction is the transfer of heat energy from one substance to another, or within a substance. Have you ever left a metal spoon in a pot of soup being heated on a stove? After a short time the handle of the spoon will become hot. This is due to transfer of heat energy from molecule to molecule or from atom to atom. We also observe this when objects are welded together; the metal becomes hot (the orange-red glow) by the transfer of heat from an arc. This is a very effective method of heat transfer in metals!
Convection is similar to conduction, except instead of transferring heat between objects, convection is the transfer of heat energy through fluids. This type of heating is most commonly seen in the kitchen when you see liquid boiling.
Test it at Home!
You can find out the thermal conductivity of different materials relatively easily at home! You’ll only need a few objects that have a flat/smooth surface. Try these for starters:
- A piece of metal
- A piece of wood
- A plastic plate
- A styrofoam plate
Place all of your materials out in the sun for about 10-15 minutes. Make sure it isn’t too windy so nothing blows away! Next, you’ll need to grab as many ice cubes as there are different materials. If you have a scale, you should measure the masses of the ice cubes to make sure they all have relatively the same mass.
“The Transfer of Heat Energy”. National Weather Service, National Oceanic and Atmospheric Administration.
Gruhl, Teodoro. “Slide”. Released into the public domain. Uploaded on 6/20/17 from publicdomainpictures.net
Seoane, Xoan. “Cooking on a Low Heat”. Released into the public domain. Uploaded on 6/20/17 from publicdomainpictures.net
“Ice Cubes for Beverages”. Released into the public domain. Uploaded on 6/20/17 from commons.wikimedia.org