Heat energy Flashcards
What is the heat rule?
Heat travels from a hotter region to a colder region
What are the 3 main methods of heat transfer?
Conduction, Convection and Radiation
Examples of conduction?
Metal object that has been heated so like
-ladle in a pot of hot soup
-spanner in the sun
-metal pot handle
What is conduction?
Heat transfer that only occurs in solids
What happens during conduction?
If flame is positioned under the solid, particles inside would start to vibrate very quickly making more energy and these particles start to bump into other particles until all the particles are vibrating. This is conduction.
What is a conductor?
Allows materials to pass through them very easily.
What is an insulator?
does not allow energy to pass through. eg wood, glass, rubber are good insulators
What is convection?
Transfer of heat through a fluid (like a liquid or a gas) because the particles spread out
What is the process of convection?
If a flame is lit, particles on bottom get more energy and move more. They take up more space and are less dense so rise to the top. The more dense paticles sink. This cycle begins.
Examples of convection:
- wind being created
-water boiling
-earths crustal plates
What is radiation?
Able to pass through a vacuum and we feel radiation from heat instantly, can occur in solds liquids and gases without particle movement as well.
When radiation occurs, what must happen?
Be transmitted- clear materials allow radiation through. Temp doesn’t rise
Be absorbed- dark colour objects, and temp rises quickly like foil
Be reflected- light colored objects reflect heat away. Temp doesn’t increase.
Do all 3 processes of radiation need to occur at the same time
yes
Does radiation need particles to transfer energy?
no
What is an insulator?
An object that does not easily allow heat, electricity, light, or sound to pass through it
