Chapter 14 Thermal Energy and Heat

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Chapter 14 Thermal Energy and Heat
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Scientist do not think about hot or cold, they
think about particles of matter in motion
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Click on the link below to see more about
temperature and the motion of particles

• http//id.mind.net/zona/mstm/physics/mechanics/en
  ergy/heatAndTemperature/gasMoleculeMotion/gasMolec
  uleMotion.html

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The warmer a substance is

• The faster the particles are moving
• Moving means kinetic energy
• The faster the particles move the more kinetic
  energy they have
• Sotemperature is a measure of the average
  kinetic energy of the individual particles in
  matter.

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Which of these would have the greater kinetic
energy
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What are the three common scales for measuring
temperature

• Fahrenheit scale
• Celsius scale
• Kelvin scale

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Try this interactive thermometer

• http//www.mathsisfun.com/measure/thermometer.html
  

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Fahrenheit scale

• F Freezing Point 32F Boiling 212 F
• Measures in degrees
• Most commonly used in the United States

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Celsius

• Used in nearly all other countries
• Measures in degrees
• Freezing point 0C Boiling 100C

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Kelvin

• Measures in Kelvins, which are the same size as
  degrees celcius
• Freezing point 273 K
• Boiling point 373 K
• -273 is absolute 0, the lowest temperature
  possible. That means no more energy can be
  removed from matter

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Take a look at this material about absolute zero

• http//www.colorado.edu/physics/2000/bec/temperatu
  re.html

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Lets practice reading themometers

• http//www.bbc.co.uk/skillswise/numbers/measuring/
  temperature/index.shtml

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Temperature, thermal energy and heat are not the
same thing.

• The total energy of the particles in a substance
  is called its_________________ energy.

thermal
The more particles an object has at a given
temperature, the more Thermal energy it has.
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Circle the letter of each sentence that is true
of thermal energy

• A. Thermal energy partly depends on the
  temperature of a substance
• B. Thermal energy partly depends on the scale
  used to measure the temperature of a substance.
• C. Thermal energy partly depends on how the
  particles of a substance are arranged.
• D. Thermal energy partly depends on the number of
  particles of a substance.

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Heat

• Thermal energy that is transferred from matter at
  a higher temperature to matter at a lower
  temperature is called heat.
• Only when thermal energy is transferred is it
  called heat.

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Specific Heat

• The amount of energy required to raise the
  temperature of 1 kilogram of a material by 1
  kelvin is called its specific heat
• Specific Heat joules per kilogram-kelvin
• J/(kgK)

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• Materials with a high specific heat can absorb a
  great deal of thermal energy without a great
  change in

temperature
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The energy gained or lost by an object is related
to which of the following

• Mass
• Volume
• Specific heat
• Change in temperature

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What is the formula you can use to calculate
thermal energy changes?

• Change in energy MassSpecific HeatChange in
  temperature