Heat Energy Transfer Flashcards
Thermal energy can be transferred through… (three things)
Conduction- solids
Convection- fluid, gasses
Radiation- vacuum
Body temperature
37°
Room temperature
21°
During heat transfer thermal energy always moves…
In the same direction
Are materials that allow heat to flow through them good or bad thermal conductors
Good thermal conductors
What is thermal conductivity
How good a material is at conducting heat
Do metals have good or bad thermal conductivity
Good
The higher the thermal conductivity of a metal the higher…
The rate of energy transfer
Materials that are poor at conducting heat are called
Poor insulators
Why are metals good conductors of heat (2 points)
They have free electrons that move faster and further when heated. They collide with cooler atoms, transferring the heat to them.
If a material has a low thermal conductivity it will give the best what?
Insulation
Why are insulators bad conductors of heat
They do not have free electrons
When an object is heated it’s temperature rises depends on
- amount of of energy
- the mass of substance
- what the substance is
Equation to work out energy
Energy transferred = mass x specific heat capacity x temperature change
(Joules). (Kg). ( joules per kg). (°C)
What does system mean
Single group or object
