A quantity of heat is transferred:

PHYSICS · Subjective · AP · Physics 2: Algebra-based · Thermodynamics · Thermodynamics

Problem

A quantity of heat

Q = 500\,\text{J}

is transferred: (a) directly from a hot reservoir at

500\,\text{K}

to a cold reservoir at

300\,\text{K}

, (b) in two equal steps, first from the

500\,\text{K}

reservoir to an intermediate reservoir at

400\,\text{K}

and then from the

400\,\text{K}

reservoir to the

300\,\text{K}

reservoir. For each case, calculate the total entropy change of the universe and show which mode of heat transfer is more irreversible.