What entropy change occurs when 800 J of energy is transfered by radiation from the sun to the earth?

The temperature at the surface of the sun is approximatly at 5700K and the temperature at the surface of the earth is approxiamtly 290 K. What entropy change occurs when 800 J of energy is transfered by radiation from the sun to the earth?What entropy change occurs when 800 J of energy is transfered by radiation from the sun to the earth?
Note: All answers are considering this particular heat transfer process alone. All other processes are ignored.



Entropy change in heat transfer is given by:

鈭哠 = 鈭玠Q/T



Because both objects are nearly isothermal throughout the process,

鈭哠 = 鈭哘/T



For the sun:

鈭哠_sun = -鈭哘/T_sun



(negative, because heat is removed from this system)



For the object of heating interest:

鈭哠_obj = 鈭哘/T_obj



For the universe (at least considering this process alone):

鈭哠_univ = 鈭哠_obj + 鈭哠_sun

鈭哠_univ = 鈭哘*(1/T_obj - 1/T_sun)



Data:

鈭哘 := 800 J; T_obj:=290 K; T_sun:=5700 K;



Results:

鈭哠_sun = -140.35 milliJoules/Kelvin

鈭哠_obj = 2.759 Joules/Kelvin

鈭哠_univ = 2.618 Joules/Kelvin



The sun removed entropy, the object gains entropy. Entropy as a net for the universe is produced in this process, thus it is an irreversible process. If mathematics indicate entropy had been destroyed in this process, it would be an impossible process.

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