Heat Transfer Flashcards
Convection
Convectionis the process of heat transfer from one location to the next by the movement of fluids.
When liquids and gases are heated the particles themselves move.
Heat can move from one place to another with which ways?
Conduction
Convection
Radiation
How does heat work?
As something rises in temperature the particles move faster or vibrate faster. And the state of matter of an object depends on this so if you heat up a solid it will turn into a liquid and then into a gas (if you continue to heat it up.)
Conduction
It’s how well an object can be overcome with vibrations and take the heat off another object. The vibrations come from the particles so the object needs to adapt to the vibrations quickly (transferring the heat to itself) to be considered a good conductor. An object that does this poorly is called an insulator.
Radiation
Heat transfer by radiation is much faster than heat transfer by conduction or convection. When heat is transferred by radiation it can do 1 of 3 things when it comes in contact with a surface. It can be absorbed, reflected or Transmitted.
What is transmitted heat?
Clear objects or substances allow radiation to pass through them. The temperature of these objects however may warm up but not much.
What is absorbed heat?
Dark coloured objects like black, can absorb light as well as radiant heat. But the temperature of these objects heats up much more quickly as the heat stays absorbed in the object.
What is reflected heat?
Objects with a shiny or bright surface like a mirror or the colour white seem to reflect light much more than a darker colour. The heat of these objects does not tend to heat up that fast because the heat only comes in contact with the surface.
