Carnot engine boiling water problem

In summary, the question involves finding the number of kilograms of ice melted in a Carnot engine given a specific amount of heat and the properties of the hot and cold reservoirs. The attempted solution involved finding the work done using the formula 1-Ql/Qh and converting it to kilograms using the Lf for water, but the resulting answer was incorrect and further assistance is needed.
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Homework Statement


A Carnot engine uses a hot reservoir consisting of a large amount of boiling water and a cold reservoir consisting of a large tub of ice and water. When 5650 J of heat is put into the engine and the engine produces work, how many kilograms of ice in the tub are melted due to the heat delivered to the cold reservoir?

Homework Equations



Melting point of water: 0C
Boiling point of water: 100C
Lf water: 33.5x10^4
Lv water: 22.6x10^5
1-(Ql/Qh)


The Attempt at a Solution



I found 1-Ql/Qh to be 1-(273/373) = 0.268 and then i multiplied that by 5650J and got 1514.75J to be the work done
Then I converted that using the Lf to get the kg so (1514.75J)/(33.5x10^4J/kg) = 0.0045kg
 
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  • #2
This answer is wrong. Can someone help me?
 

1. What is the Carnot engine boiling water problem?

The Carnot engine boiling water problem is a theoretical scenario used in thermodynamics to explain the limitations of heat engines. It involves a heat engine operating between two reservoirs at different temperatures, with one reservoir at the boiling point of water. The goal is to determine the maximum efficiency that the engine can achieve.

2. Why is the Carnot engine boiling water problem important?

This problem is important because it helps to illustrate the concept of maximum efficiency in heat engines. It also highlights the significance of the Carnot cycle, which is a theoretical construct used to model idealized heat engines.

3. What are the assumptions made in the Carnot engine boiling water problem?

The problem makes several assumptions, including the idea that the heat engine is operating in a reversible manner, meaning that it can be run in both forward and reverse directions with no loss of efficiency. It also assumes that the engine is in thermal equilibrium with the two reservoirs and that there are no other sources of energy or work involved.

4. How is the efficiency of the Carnot engine determined in this problem?

The efficiency of the Carnot engine is determined by the temperature of the two reservoirs. It is given by the formula: efficiency = 1 - (T1/T2), where T1 is the lower temperature and T2 is the higher temperature. In the boiling water problem, T1 would be the boiling point of water and T2 would be the temperature of the other reservoir.

5. What is the significance of the results obtained from the Carnot engine boiling water problem?

The results obtained from this problem show that the maximum efficiency of a heat engine is dependent on the temperature difference between the two reservoirs. It also demonstrates that no real heat engine can achieve 100% efficiency, as there will always be some energy lost due to the Second Law of Thermodynamics.

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