Answer:
292.984 K or 19.98 °C
Explanation:
Using,
η = Tc/(Th-Tc)................ Equation 1
Where η = coefficient of performance, Tc = cold temperature of the refrigerator, Th = hot temperature of the refrigerator.
Make Th the subject of the equation
η (Th-Tc) = Tc
η Th-η Tc = Tc
Th = (Tc+ηTc)/η ....................... Equation 2
Given: Tc = -13.5°C+273 = 259.5 °C, η = 7.75
Substitute into equation 2
Th = (259.5+7.75×259.5)/7.75
Th = (259.5+2011.125)/7.75
Th = 2270.625/7.75
Th = 292.984 °C or 19.98 °C
Hence the maximum hot reservoir temperature = 292.984 °C or 19.98 °C
