Air Conditioners and Refrigerators

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Air Conditioners and Refrigerators
 
The second law explains how the Universe is continuously slipping
The second law explains how the Universe is continuously slipping
into chaos. This does not mean that there cannot be (on a local scale) a
into chaos. This does not mean that there cannot be (on a local scale) a
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order, but creating order without causing even more disorder somewhere
order, but creating order without causing even more disorder somewhere
else (usually in the neighborhood).
else (usually in the neighborhood).
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Air conditioners and refrigerators are devices that move heat away from
Air conditioners and refrigerators are devices that move heat away from
a space in defiance of the common perception that heat moves from a
a space in defiance of the common perception that heat moves from a
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additional energy in terms of electricity and creation of disorder outside
additional energy in terms of electricity and creation of disorder outside
the immediate neighborhood of these devices.
the immediate neighborhood of these devices.
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The operation of these devices can be best described as the heat engines
The operation of these devices can be best described as the heat engines
operating in reverse. Heat is removed from the space (inside the refrigerator
operating in reverse. Heat is removed from the space (inside the refrigerator
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reservoir is the kitchen. In the case of the air-conditioner, it is the outside
reservoir is the kitchen. In the case of the air-conditioner, it is the outside
air. Energy input in the form of electricity or heat is needed to make the
air. Energy input in the form of electricity or heat is needed to make the
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uphill transfer of heat possible (Figure 5-8).
+
uphill transfer of heat possible (Figure 1).
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[[Image:energy5_(19).jpg |thumb|400 px|alt= Refrigerator | Figure 1: Refrigerator  ]]
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5-8
==References==
==References==

Revision as of 22:42, 16 July 2010

The second law explains how the Universe is continuously slipping into chaos. This does not mean that there cannot be (on a local scale) a transformation from chaos to order. In fact, this is the main mechanism by which we can defy nature. When we build houses, we change the randomly distributed bricks, lumber, and clay into structured walls of living rooms, bedrooms, and kitchens. We bring order into our house by cleaning it. What the second law precludes us from doing is not creating order, but creating order without causing even more disorder somewhere else (usually in the neighborhood).

Air conditioners and refrigerators are devices that move heat away from a space in defiance of the common perception that heat moves from a higher to a lower temperature. The price is of course the expenditure of additional energy in terms of electricity and creation of disorder outside the immediate neighborhood of these devices.

The operation of these devices can be best described as the heat engines operating in reverse. Heat is removed from the space (inside the refrigerator or air-conditioned room) and dumped into a second reservoir at a higher temperature. In the case of the household refrigerator, the second reservoir is the kitchen. In the case of the air-conditioner, it is the outside air. Energy input in the form of electricity or heat is needed to make the uphill transfer of heat possible (Figure 1).

File:Energy5 (19).jpg
Figure 1: Refrigerator

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References

Further Reading

External Links