Heating a Cabaret during the winter

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Heating a cabaret in winter requires a climate control system to efficiently transfer heat from the outside air, which necessitates the use of electricity. Heat naturally flows from warmer to cooler areas, so moving heat against this gradient is not spontaneous and requires ordered energy. The discussion highlights that option D is the most accurate explanation, as it emphasizes the increase in entropy when heat moves from the colder outdoor air to the warmer cabaret air. A clarification was made regarding option C, confirming that it correctly states heat does not flow from cold to hot without energy input. Overall, the conversation centers on the principles of thermodynamics and energy transfer in heating systems.
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Homework Statement


During the winter, your climate control system must begin warming the cabaret air so that the cabaret air is hotter than outdoor air. Amazingly enough, it can do this relatively efficiently by transferring heat from the outside air into the cabaret. However, your system must use electricity to carry out this heat transfer. Why won't the heat transfer occur naturally?
Select one:
a. Heat tends to flow naturally from inside to outside. Transporting heat against its natural direction of flow requires the consumption of ordered energy.
b. Although heat tends to flow from hotter to colder, moving that heat from place to place requires the conversion of ordered energy (such as electricity) into thermal energy.
c. Heat doesn't flow naturally from cold to hot because that would produce a decrease in entropy.
d. As each joule of heat moves from the colder outdoor air to the warmer cabaret air, the entropy of the cabaret air increases by more than the entropy of the outdoor air decreases. To obtain that increase in entropy, some electrical energy must be converted to thermal energy.

Homework Equations


N/A

The Attempt at a Solution


D, because in A, heat does not naturally flow from inside to outside. In B, heat should tend to flow from hot to cold regardless of electrical energy. In C, heat does flow from hot to cold leaving that one completely wrong. This leaves D, as it is the only one that makes sense I believe.
 
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Dreebs said:
In C, heat does flow from hot to cold leaving that one completely wrong.
Read C more carefully.
 
haruspex said:
Read C more carefully.
Whoops! Somehow read it backwards. With that change, would that then make C the correct answer since heat doesn't flow naturally from cold to hot.
 
Dreebs said:
Whoops! Somehow read it backwards. With that change, would that then make C the correct answer since heat doesn't flow naturally from cold to hot.
Right.
 
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