5 ### Thermodynamics Problems for Educational Purposes#### Problem 5**(15.22)** A heat engine's high temperature \( T_H \) could be ambient temperature because liquid nitrogen at 77 K could be \( T_L \) and is cheap. What would be the efficiency of a Carnot engine that made use of heat transferred from air at room temperature (293 K) to the liquid nitrogen "fuel"?#### Problem 6**(15.32)** If an ideal refrigerator keeps its contents at 2.5°C when the house temperature is 22°C, what is its COP (Coefficient of Performance)?#### Problem 7**(15.39)** What is the change in entropy of 320 g of steam at 100°C when it is condensed to water at 100°C?### Explanation of Concepts#### Carnot Engine EfficiencyThe efficiency \(\eta\) of a Carnot engine is given by the formula:\[\eta = 1 - \frac{T_L}{T_H}\]where \( T_H \) is the high temperature reservoir and \( T_L \) is the low temperature reservoir. Both temperatures must be in Kelvin.#### Coefficient of Performance (COP) of a RefrigeratorThe Coefficient of Performance (COP) for a refrigerator is given by:\[COP = \frac{T_L}{T_H - T_L}\]where \( T_L \) is the temperature inside the refrigerator and \( T_H \) is the ambient temperature. Both temperatures must be converted to Kelvin.#### Change in EntropyThe change in entropy \(\Delta S\) when steam condenses to water is calculated by:\[\Delta S = \frac{Q}{T}\]where \( Q \) is the heat released during condensation, and \( T \) is the temperature at which the process occurs (in Kelvin).### Example Calculations#### Problem 5Given:- \( T_H = 293 \) K (room temperature)- \( T_L = 77 \) K (temperature of liquid nitrogen)The Carnot efficiency:\[\eta = 1 - \frac{77}{293}\]#### Problem 6Given:- \( T_L = 2.5^\circ \text{C} = 275.65 \) K- \( T_H = 22^\circ \text{C} =

Answered: Image /qna-images/answer/c0acf8ad-a009-41b3-984a-28f262206df1.jpg

5. (15.22) A heat engine's high temperature TH could be ambient temperature, because liquid nitrogen at 77 K could be Ti and is cheap. What would be the efficiency of a Camot engine that made use of heat transferred from air at room temperature (293 K) to the liquid nitrogen "fuel"?