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Thermal Energy & Thermal Energy & HeatHeat
THERMAL ENERGY & MATTER: Journal
1. In which direction does heat flow spontaneously?2. Define TEMPERATURE3. How is THERMAL ENERGY transferred?4. What are the factors that determine the THERMAL
ENERGY of a material?5. Which type of material heats more, one with a
high specific heat, or one with a low specific heat?6. Is WORK 100% efficient? How do you know?
THERMAL ENERGY & MATTER
Work and Heat- work is never 100% efficient. Some is always lost to heat.
THERMAL ENERGY & MATTER
Heat- the transfer of thermal energy from one object to another because of a temperature difference.
In what direction does heat flow spontaneously?
FROM HOT to COLD
THERMAL ENERGY & MATTER
Temperature = measure of how hot or cold something is compared to a reference point.
Temperature is the average kinetic energy of the particles in an object.
In the image below, where is average kinetic energy greater?
Higher temperature
THERMAL ENERGY & MATTER
Thermal energy- total potential and kinetic energy in an object. It depends on mass, temperature, and phase of an object.If both objects are in the same phase & at the same temperature, which one has MORE thermal energy?
Because thereare MORE
particles moving around.
THERMAL ENERGY & MATTER
Specific Heat – amount of heat needed to raise ONE gram of a material ONE degree Celsius.
THERMAL ENERGY & MATTER
The LOWER a material’s specific heat the MORE its temperature rises when energy is added.Which will heat faster (has the lower specific
heat)?Water? Or Lead?
YES!
Specific heat of water = 4.18 J/g°C Specific heat of lead = 0.46J/g°C
3 methods of heat transfer: conduction, convection, and radiation.
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Heat Transfer:
Crust forming on the surface of lava is an example of a change of state by transferring heat from the hot lava to the cooler air surrounding the lava.
HEAT TRANSFER
What type of HEAT TRANSFER is occurring in the pictures? Conduction, convection or radiation?
CONDUCTION – The transfer of thermal energy with no
transfer of matter. Must be Touching!
HEAT TRANSFER
What type of HEAT TRANSFER is occurring in the pictures? Conduction, convection or radiation?
CONVECTION – The transfer of thermal energy when particles
of a liquid or gas move from one place to another
HEAT TRANSFER
CONVECTION – in the earth and sun
HEAT TRANSFER
What type of HEAT TRANSFER is occurring in the pictures? Conduction, convection or radiation?
RADIATION – The transfer of thermal energy by waves
moving through space. ALL OBJECTS radiate energy!
THERMAL ENERGY & MATTER: Journal
1. Define Convection, Conduction and Radiation
2. Give an example of each.3. Write a sentence describing how each
is important to our everyday lives.4. How do we use heat in our everyday
lives?
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Where does heat transfer on this beach?
Label at least four examples of heat transfer on the
picture.
Diagram Answers:
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Methods of Heat Transfer
Think-Pair-Share!!Discuss examples
of each type of heat transfer with a partner for two minutes.
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Methods of Heat Transfer
Conduction:
Heat transferred by touching
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Convection: Heat transferred by the motion of a substance
Radiation: Heat transferred through as waves through space