Concordia University

PHYS 273

LESSON 3

1)Generators convert ….

2. Heat engines convert…
3. If the engine in your car produces 30 joules of useful work for every 100 joules of gasoline used, what is its efficiency?
4. T or F: As the entropy of a system increases, the total amount of useful energy decreases.
5. T or F: In an isolated system the entropy of the system increases over time.
6. Which is NOT a main product in the combustion of hydrocarbons?
7. The amount of energy released per 100 grams of fuel burned in a reaction is called…
8. The change in the internal energy of a system equals the net heat transfer into the system minus the net work done by the system. This is…
9. Using the heat source and heat sink temperatures for a heat engine, you can calculate that the best efficiency is 60%. This means…
10. T or F: Without a temperature difference between heat source and heat sink, it is impossible to run a heat engine.
11. A battery contains 1000 joules of energy. The maximum amount of work it can do is 1000 joules. This is an example of…
12. A process that occurs spontaneously in one direction only is called…
13. Which has a lower entropy…
14. T or F: For heat engines, the larger the temperature heat difference between a heat source and heat sink, it is impossible to run a heat engine
15. Currently, the best electrical power plants have efficiencies around…

16. The measure of randomness, or disorder, of a system is called…
17. T or F: Entropy never spontaneously increases.