PHYS 2133
Chapters 12 - 15


Chapter Objectives

  1. Define temperature and describe its relationship to heat and energy.
  2. Define specific heat, heat of vaporization, and heat of fusion.  Use these definitions to determine the final temperature when objects of different temperature come into thermal contact.
  3. List and define the three types of heat transfer.
  4. Define and use the Ideal Gas Law for monatomic gases.
  5. List and define the laws of thermodynamics.  Define entropy.
  6. Differentiate between a heat engine and a heat pump.  Define the efficiency and maximum efficiency of a heat engine.

Conceptual Questions

  1. Is it possible for two objects to be in thermal equilibrium with each other and to not be touching?
  2. Why is a chimney never used as a load-bearing structure in a house?
  3. Why should a baking potato be pricked with a sharp object before cooking begins?
  4. What happens to a balloon placed in a refrigerator?
  5. Ethyl alcohol has about 1/2 the specific heat of water. If equal masses of alcohol and water in separate beakers are supplied with the same amount of heat, compare the temperature increases of the two liquids.
  6. What is wrong with the following statement: "Given any two bodies, the one with the higher temperature contains more thermal energy."?
  7. To protect their fruit crop from hard freezes, orange growers will often spray a mist of water on the trees. What does this do to protect the fruit?
  8. Is it possible to convert internal energy to mechanical energy?
  9. Is it possible to construct a heat engine that creates no thermal pollution?
  10. Can a heat pump have a coefficient of performance less than one?   

Problems

  1. The pressure in a constant-volume gas thermometer is 0.700 atm at 100oC and 0.512 atm at 0oC. (a)What is the temperature when the pressure is 0.0400 atm? (b) What is the pressure at 450 oC?
  2. One mole of oxygen gas is at a pressure of 6.0 atm and a temperature of 27 oC. (a) If the gas is heated at constant volume until the pressure triples, what is the final temperature? (b) If the gas is heated so that both the pressure and volume are doubled, what is the final temperature?
  3. A 0.40-kg iron horseshoe that is initially at 500 oC is dropped into a bucket containing 20 kg of water at 22 oC. What is the final equilibrium temperature? Neglect any heat transfer to or from the surroundings.
  4. A student claims that she has constructed a heat engine that operates between the temperatures of 200 K and 100 K with 60% efficiency. The professor does not give her credit for the project. Why not?

 

Solutions

If you find an error in these, or just have a comment, send an e-mail message to jpratte@kennesaw.edu