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The highest coefficient of performance that a heat pump operating between two reservoirs can have is:

-0% or 0.00
-equal to that of an irreversible heat pump
-100% or 1.00
-equal to that of a Carnot heat pump

User Palo Misik
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1 Answer

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Final answer:

The coefficient of performance (COP) of a heat pump operating between a hot reservoir at 45.0°C and a cold reservoir at -15.0°C is best determined using a Carnot heat pump model, which is a reversible heat pump operating between two temperatures and represents the theoretical maximum efficiency of a heat pump.

Step-by-step explanation:

Understanding the Coefficient of Performance of a Heat Pump

The question at hand concerns the coefficient of performance (COP) of a heat pump when it operates between two specific temperatures. For a heat pump operating with a hot reservoir at 45.0°C and a cold reservoir at -15.0°C, we must use thermodynamic principles to determine its maximal efficiency. According to thermodynamics, the highest COP a heat pump can achieve is equivalent to that of a Carnot heat pump, which is an idealized heat pump operating between two temperatures with no entropy production (reversible process).

To compute the COP for a Carnot heat pump, one must use the absolute temperatures in Kelvin. For the given temperatures, the hot reservoir (Th) is 45.0°C, or 318.15K, and the cold reservoir (Tc) is -15.0°C, or 258.15K. The COP of a Carnot heat pump is calculated using the equation COPhp = Qh/W = Th/(Th - Tc), where Th and Tc are the absolute temperatures of the hot and cold reservoirs respectively, and W represents the work input required.

Thus, the best achievable COP for an ideal heat pump operating between these temperatures could be calculated, which represents the most efficient transfer of heat from the cold to the hot reservoir for a given amount of work. The Carnot heat pump provides a theoretical upper limit to the performance of real heat pumps.

User Jacques Betancourt
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