Another heat engine efficiency problem

AI Thread Summary
To determine how long it takes to freeze 1.10 kg of water at 0°C using a reversible heat engine operating at 183 W, the energy required for the phase change must be calculated. The latent heat of fusion for water is necessary to find the total energy to be removed. Power, defined as energy per unit time, can then be used to calculate the time needed for the freezing process. By dividing the total energy required by the engine's power output, the time to freeze the water can be determined. Understanding these concepts is crucial for solving the problem effectively.
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A reversible heat engine has an efficiency of 34.2%, removing heat from a hot reservoir and rejecting heat to a cold reservoir at 0°C. If the engine now operates in reverse, how long would it take to freeze 1.10 kg of water at 0°C, if it operates on a power of 183 W?



I am getting stuck on how I can incorporate the kg of water and the power.
I don't know which equation to use that will let me use those constants and allow me to find time.
 
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Well, to freeze water, you have to remove thermal energy from it. How do you find the amount of energy needed to be removed for a phase change of the water at 0°C to ice at 0°C?
It gives you the power the engine is operating at. What is the definition of power?
I'd think about those things to start.
 
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