1.1 - Heat Transfer Flashcards
What do all objects do?
Emit and absorb infrared radiation
How does temperature effect the amount of infrared radiation emitted?
The hotter an object is the more infrared radiation it radiates
How do dark, matt surfaces effect radiation?
Good absorbers and good emitters of infrared radiation
How do light, shiny surfaces effect infrared radiation?
Poor absorbers, poor emitters and good reflectors of infrared radiation
In a hot country what colour would they paint the house to limit temperature inside?
White
What colour should radiators be painted to maximise heat to the room?
Black matt as it would be better at absorbing and emitting the heat to a room
What is the kinetic theory?
It explains the properties of the different states of matter
Describe a solids properties
Fixed and close regular patterns Vibrate on a fixed position Compact Dense Strong bonds Large resistance Large volume Can't compress
Describe a liquids properties
Slightly random pattern Vibrating moderately The bonds are together but not as strong Some resistance Can't compress Takes the shape of container as particles move around each other
Describe a Gases properties
Lots of space between particles Vibrates a lot Travel at a thousand miles per second Minimal resistance Minimal to no existent bonds Easy to compress
What is the main difference between solids, liquids and gases?
They all have different amounts of energy
What is conduction
Heat transfer through solids
How does conduction work?
In metals there are delocalised electrons that surround positive ions
The electrons gain kinetic energy when heated vibrating faster
The electrons collide with each other transferring the kinetic energy
What name is given to a material that allows electrical currents to pass through?
A conductor
Why don’t non-metals conduct electricity?
They don’t have delocalised electrons
