Concept explainers
The heat engines among the motor engines.
Answer to Problem 1CQ
choice (a) an automobile engine and (c) a steam turbine.
Explanation of Solution
In
Write an expression for the heat input from the hot reservoir,
Here,
Conclusion:
In an automobile, an internal combustion engine is developing heat internally. This heat is converted into mechanical work. Since the heat is developed internally, extraction of heat from an external source does not occur. Thus, choice (a) is correct.
The steam turbine has an external combustion engine. Here, the engine obtains the energy to produce the superheated steam from heating outside of the turbine. Thus, choice (c) is correct.
In electrical motors, conversion of electrical energy to work occurs. Thus, choice (b) is incorrect.
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Chapter 11 Solutions
Physics of Everyday Phenomena
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