Conduction and radiation Flashcards
What are the best conductors?
Metals with a high energy transfer
What are non-metals?
Insulators with a low energy transfer
What is convection?
The movement of heat in fluids
What do the particles in the fluid do when hot?
Become less dense, rise and float
What do the particles do when cold?
Become denser and sink
What do all hot objects radiate? What is there no need for?
Heat in the form of waves, no need for particles
Why are houses insulated?
To prevent energy loss and save energy resources and money
What does double-glazing prevent?
Heat loss
How does double-glazing prevent heat loss?
There is a trapped layer of gas which disrupts conduction and convection cycles
What are insulating panels made from?
Made of a foam and coated with foil
What do insulating panels do?
Reduce radiation, conduction and convection
What do all objects emit and absorb?
Radiation, the hotter the more is given out
What does the earth’s temperature depend on?
Radiation from the sun
What does increasing the number of layers of insulation do?
Decreases the thermal transfer so the temperature loss is less
Why are materials with trapped layers of air good insulators?
Because heat does not transfer well between solids and gases
