- Conduction: Transfer of heat energy through a substance without itself moving
- It is when atoms vibrate and heat is transferred from one atom to another
- It is when electrons move from hot –> cold
- Metals are good conductors of heat because this movement is faster, as the electrons are free to move
- An increase in temperature = Increase in the average amount of movement/energy vibration
- Convection: The transfer of heat energy through fluids (liquids and gasses) by the upward movement of warmer, less dense regions of fluid
- When a gas or liquid is heated, it expands. As most fluids are poor thermal conductors, it happens to the closest source of heat
- PROCESS OF EXPANSION: Density of the fluid reduces and floats upwards (Warmer fluid). Pushed out of the way by colder, denser fluid.
- Cold water is more dense than hot water.
- Radiation: Transfer of heat energy in the form of infrared waves
- Radiation is the only method of heat transfer through a vacuum
- Energy is transferred by electromagnetic, infrared waves at the speed of light
- Dull, dark surfaces absorb the infrared radiation faster and are better emitters of radiation (They cool down faster)
- Shiny, bright surfaces reflect radiation and absorb much less of it (much slower to cool down)