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