Thermal Flashcards
What is conduction
Transfer of thermal/heat energy by vibrations/KE
Example of a good conductor
Metals due to free electrons
What is convection
Transfer of heat in liquids and gasses due to changes in density when the fluid is heated or cooled - establishes convection current
What’s a convection current
A way for heat to travel eg when water turns to steam
What is radiation
Transfer of energy by (electromagnetic) waves - no particles involved so it is the only method of heat transfer through a vacuum
What’s an example of radiation
Infra red or x rays
What’s a vacuum
An area containing no particles
What’s an emitter or an absorber
Absorbs energy or particles
Emits energy or particles
What’s an example of an emitter or an absorber
Dark matter
What’s the particle lay out of a solid
Particle tightly packed
Particle in fixed position
Particle vibrate but don’t move
What’s the particle layout of a liquid
Particle are close together
Particle don’t have a fixed position
Can move and vibrate into/around each other
What’s the particle lay out of a gas
Partials can move freely
Why does convection happen
When heated fluids expand the amount of fluid increases and the density decreases
Causes gas to rise
Cooler fluid flows in to replace it
Worst emitter and absorber
Shiny light but it is the best reflector
