Physics

Problem

A heat engine operates in a single cycle by absorbing

600\,\text{J}

of energy as heat from a hot reservoir at

500\,\text{K}

and ejecting

400\,\text{J}

of energy as heat to a cold reservoir at

300\,\text{K}

. Which statement about the change in entropy of the universe

\Delta S_{\text{univ}}

during this cycle is most accurate? a)

\Delta S_{\text{univ}}<0

, so the cycle violates the second law. b)

\Delta S_{\text{univ}}>0

, so the cycle is irreversible but permissible. c)

\Delta S_{\text{univ}}=0

, so the cycle is reversible. d)

\Delta S_{\text{univ}}>0

, so the cycle is impossible.