Work can create heat but heat can't create work

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In summary, the conversation discusses the refinement of terms in thermodynamics and how it affects the transfer of energy between hot and cold containers of water. The first and second laws of thermodynamics are mentioned, as well as the concept of constant enthalpy process. The conversation also touches on the possibility of heat being used to generate electrical energy. The main problem with this approach is that heat is not considered to be able to do work in traditional thermodynamics.
  • #1
wrenchtime
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Suppose we refine some of terms in thermodynamics based on the follow statements:
1. All energy has two components: work energy and heat energy.
2. Work is the change in work energy which is equal to the energy available to do work.
3. Heat is the change in heat energy which is equal to the energy unavailable to do work.
4. Work can create heat but heat can not create work.

How would these changes effect the transfer energy between a hot(h) and cold(c) containers of water?

The hot container is a higher energy state therefore it holds more work energy than the cold container.
Therefore the energy transfer is:

First law:
Energy (hot)(-) + Energy (cold)(+) = 0
(Energy release from hot container is equal to energy absorbed by the hot container)

Second law:
The change in work energy (hot) is greater than the change in work energy (cold)
Or work done by the (hot) is greater than the work absorbed by the (cold)
Work (hot)(-) + Work (cold) (+) = Total system work change(-)

The change in heat energy (hot) is less than the change in heat energy (cold)
Or heat (hot) is less than the change in heat energy (cold)
Heat (hot)(-) + Heat (cold) (+) = Total system heat change (+)

Summary:
To maintain the first law the total change in Energy must be zero, therefore
Total system work change (-) + Total system heat change (+) must be equal to zero

Another example of this is the constant enthalpy process. (throttling)
During this process the energy change is zero but
the energy available to do work (Work) is converted to energy unavailable to do work (Heat).

With this approach the entropy and the total system heat change both increase during the transfer of energy between two medium.
Also this would apply to all energy (potential, kinetic and etc.)

What are the problems with approach?
 
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  • #3
Heat can do work, that is the basis of all heat engines.

We do not do personal speculation. If you have questions about mainstream thermodynamics then you are free to ask them here, but not speculate on possible changes to thermodynamics.
 

What does "Work can create heat but heat can't create work" mean?

This phrase is based on the first law of thermodynamics, which states that energy cannot be created or destroyed, only transferred or converted from one form to another. In this context, it means that work (the transfer of energy from one object to another) can result in the production of heat, but heat alone cannot be converted into work.

How is heat created from work?

When work is done on an object, its energy increases, resulting in an increase in its temperature. This increase in energy is manifested as heat, which is a form of thermal energy. This is because the work done on the object causes its molecules to move faster and collide with each other, resulting in an increase in temperature.

Why can't heat be converted into work?

Heat is a form of energy that flows from a hotter object to a cooler object. In order for work to be done, there must be a difference in energy levels, and heat alone cannot provide this difference. Additionally, the conversion of heat into work would violate the first law of thermodynamics, as it would mean creating energy out of nothing.

What are some examples of work creating heat?

There are many examples of work creating heat in everyday life. For instance, when you rub your hands together, the friction between them results in the production of heat. When you use a pencil sharpener, the work done by turning the handle causes the pencil to heat up. Similarly, when you use a hand-cranked generator, the work done by turning the crank produces heat in the wires that power the light bulb.

Does this mean that heat is a waste product?

While heat is often thought of as a waste product, it is actually an essential component of many processes. For example, in a car engine, the combustion of fuel produces heat, which is then converted into mechanical work to power the car. In a power plant, heat is used to boil water and produce steam, which then turns turbines to generate electricity. So, while heat cannot be converted back into work, it is still an important form of energy that can be harnessed for various purposes.

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