Thermal Energy Transfer
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Transcript of Thermal Energy Transfer
THERMAL ENERGY TRANSFER
Thermal Energy Transfer Thermal Energy can be
transferred by three methodsConductionConvectionRadiation
Conduction Conduction is the transfer of thermal
energy by contact between particles of matter from a high temperature to a low temperature
Heat moves faster through solids and liquidsThis is because the particles are
closer together
Convection Convection is the transfer of thermal energy
by the partcles of a fluidFluids are liquids and gasesCurrents transfer heat from high
temperature to low temperatureAs a fluid heats up it expands and
becomes less denseThis heated fluid will then rise above fluid
of a lower temperature
Radiation Radiation is the transfer of energy by
electromagnetic wavesIt can travel through space where
there is no matterThis is radiant energy
Radiation
Materials can absorb, reflect, or transmit radiationDark colors absorb radiationLight colors reflect radiation
Radiation can pass through the particles that make up solids liquids and gases
Insulators An insulator is a substance that heat
flows slowly through They will have a high specific heat Gases make good insulators because
they do not conduct heat well
THERMODYNAMICS
Using Heat On of the most basic ways of using heat
is to heat your home Most homes used a forced air system
that pumps warm air into a room and heat the room by convection
Radiators Older buildings may use radiators A radiator uses steam to heat rooms by
convection
Thermodynamics You can increase the thermal energy of
an object with out adding heat
Thermodynamics is the study of the relationship between thermal energy, heat, and work
1st Law of Thermodynamics The increase in thermal energy of a
system equals the work done on the system plus the heat transferred to the system
2nd Law of Thermodynamics It is impossible for heat to flow from a
cool object to a warmer object unless work is done.
If you hold ice in your hand, heat flows from you to the ice cube
Engines Heat can be converted into work A heat engine is a device that turns heat
into work It is impossible to make an engine that
completely converts heat into work This is because it will violate the second
law of thermodynamics