Can dissipated energy be harnessed through repeated friction?

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The discussion centers on the hypothetical scenario of harnessing energy from repeated friction, specifically using sandpaper on wood. It concludes that while heat generated from friction can transfer to air molecules, this process cannot overcome the second law of thermodynamics, which states that energy transformations are never 100% efficient and always result in wasted heat. The conversation emphasizes that any attempt to use dissipated energy will ultimately lead to a loss of usable energy due to the inevitable equalization of temperature between heat sources.

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hammertime
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This is a hypothetical question. Suppose you were to run a piece of sandpaper over a piece of wood repeatedly and quickly, thus heating the surface of the wood. The wood would then transfer that heat to the local molecules in the air, right? Could that energy which is transferred to the molecules somehow be harnessed? Couldn't this be a way to overcome the second law of thermodynamics?
 
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Yes, it would. And since you can't "overcome the second law of thermodynamics"...

References to using heat to do work depend upon there being a two different sources of heat, one being hotter than the other. Since that is, in a sense, a "structure", the situation is not completely random, you can do work by transferring heat from the hotter to the cooler. Of course, that then destroys the "structure", eventually reducing both sources to the same temperature.
 
All the 2nd law tells you is that there is always going to be wasted heat. Even if you recover it, the next process you use it in is still going to waste some.
 

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