The Prime Movers

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The Prime Movers

• Temperature in Thermal Systems

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• Thermal Energy
• The total energy of the thermal motion of all the
  particles that make up an object

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• Temperature
• A. hotness
• B. The average kinetic energy of the random
  motion of the atoms and molecules in a body

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• Measuring Temperature
• A. Thermometeruses expansion and contraction
  of a liquid to measure temperature
• B. Thermal equilibriumwhen temperatures become
  equal because of energy flow from a substance
  with higher temp. to a substance with lower temp.

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C. Celsiusfreezing point of water is 0C
boiling point is 100C D. Fahrenheit--freezing
point of water is 32F boiling point is
212F E. TC 5/9 (TF-32) F. TF 9/5 TC 32
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• Heat
• A. Conductionthermal energy flows from hotter
  object to cooler object by colliding
  particlesTOUCH
• B. Heatenergy that flows because of a
  temperature difference
• C. Temperature Difference is the prime mover in
  thermal systems

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• Specific Heat
• A. Units
• 1. jouleSI
• 2. calorieamount of thermal energy it takes
  to change the temp. of 1g of water by 1 C
• 3. Btuamount of thermal energy it takes to
  change the temp. of 1 lb of water by 1 F

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• B. Specific heatamount of energy that must be
  added to raise the temp of a unit mass of the
  substance one temp. unitbased on water as 1
• 1. Q mC?T
• 2. transferred heat mass x specific heat x
  change in temp

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• C. Change of State
• 1. boiling pointtemp needed to change a
  liquid to a gas
• 2. heat of fusionamount of energy needed to
  melt one gram of a solid
• 3. heat of vaporizationthe amount of energy
  needed to vaporize one gram of a liquid

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4. Q mHfamount of heat needed to melt a
solid heat mass x heat of fusion 5. Q
mHvamount of heat needed to vaporize a
liquid heat mass x heat of vaporization