THERMAL ENERGY AND HEAT

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THERMAL ENERGY AND HEAT

• Jennefer Cardenas

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Objectives

• Students will be able to identify and know
  difference between THERMAL ENERGY, TEMPERATURE,
  and HEAT.
• Students will be able to identify the 3 ways heat
  is transferred.
• Students will be able to compare different
  conductors and insulators.
• Students will be able to compare Celsius and
  Fahrenheit Scale.

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TEMPERATURE

• The measure of the average kinetic energy of the
  individual particles in an object.
• Matter is made up of tiny particles called atoms
  and molecules. These particles are always in
  motion even if the object they make up isnt
  moving at all. Energy of motion is called
  kinetic energy, so all particles of matter have
  kinetic energy. The faster the particles are
  moving, the more kinetic energy they have.

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WATER AND DYE EXPERIMENT

• Why did the dye in hot water move faster than the
  dye in cold water?
• The results have to do with the different
  temperatures of the water.

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Back to Experiment

• So what explanation would be given if we heated
  the cold water.
• Its particles will start moving faster, so their
  kinetic energy will increase. This means that
  the temperature of the water will rise.

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THERMAL ENERGY

• The total energy of all the particles.
• If 2 samples of matter are at the same
  temperature they do not necessarily have the same
  total energy.

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What is Heat?How is heat transferred?

• Heat is thermal energy moving from a warmer
  object to a cooler object.
• There are 3 ways that heat can move.
• Conduction
• Convection
• Radiation

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CONDUCTION

• Heat conduction or thermal conduction is the
  transfer of thermal energy through matter, from a
  region of higher temperature to a region of lower
  temperature, and acts to equalize temperature
  differences.
• It is also described as heat energy transferred
  from one material to another by direct contact.

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CONVECTION

• Convection is the movement of molecules within
  fluids ( a liquid or a gas) the warm fluid rises
  and cooler fluids flow in to replace it. This
  creates a circular flow.

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More Convection

• The wind we feel outside is often the result of
  convection currents. You can understand this by
  the winds you feel near an ocean. Warm air is
  lighter than cold air and so it rises. During the
  daytime, cool air over water moves to replace the
  air rising up as the land warms the air over it.
  During the nighttime, the directions change --
  the surface of the water is sometimes warmer and
  the land is cooler.

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RADIATION

• The transfer of energy by electromagnetic waves.
• Radiation does not require matter to transfer
  thermal energy.

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Radiation

• The sun's rays travel in straight lines called
  heat rays. When it moves that way, it is called
  radiation.
• When sunlight hits the earth, its radiation is
  absorbed or reflected.

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Conductors and insulators

• A conductor is an object that can conduct heat
  well
• An insulator is an object that conducts heat
  poorly.

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ASSESMENT

• What are the 3 ways heat is transferred
• Convection, Conduction, and Radiation
• TRUE or FALSE The transfer of energy by
  electromagnetic waves is the definition for
  Convection
• False
• TRUE or FALSE In this picture B is representing
  a heat conductor and A is representing heat
  convection?
• True