Flashcards
heat transfer- conduction, convection, radiation
Flashcards do conjunto (6)
- 1Conduction - transfer of heat in solids - high temperature => low temperature - flow stops when temperature is equalParticle model of conduction
- particles move closer to heat source => vibration
- particles bump into those next to them and transfer energy
- as this continues to happen heat energy spreads through the substance - 2—Good conductors of heat
- things that conduct well are called 'good conductors'
most metals are good conductors
eg. copper, iron, aluminium
- they are good thermal conductors- that's why we use them as cooking utensils - 3Convection - method of heat transfer in gas or liquid - requires substances that flow - cannot happen in solidsParticle model of convection
- hot liquids and gases rise when heated
- as particles gain energy the expand
- causes the substance to get less dense
- eg: when boiling water, water is heated and becomes steam, and the steam rises. - 4Movement of gas or fluid by convection is also known as 'convection current'Example
- 5Radiation - all objects emit heat through infra-red radiation - the more heat an object contains, the more infra- red radiation it gives off - the sun's heat reaches the earth through radiationParticle model of radiation
- no particles are involved in heat radiation
- which is why it works in space
- this type of heat transfer does not require any medium - 6Objects : Absorption - dark surfaces absorb more heat than light surfaces - shiny surfaces reflect more heat than dull surfaces.
Informações
- Descrição
- This describes the main processes of heat transfer in the 3 states of matter.
- Criado por
- Thalia Grace
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