Question

) Circle the valid phrase(s) about the Kelvin-Planck Statement: (A) It is possible for a device to operate on a cycle to receive heat from a single reservoir and produce

a net amount of work. (B) Thermal efficiency of a heat engine could reach 100% if no friction is involved. (C) A net positive work can be output by a device that adsorbs energy from a high temperature reservoir without ejecting energy to a low temperature reservoir. (D) Mechanical work can always be converted to heat directly and completely, and the reverse is true. (E) It is necessary to have a low temperature reservoir to reject waste heat energy for a heat engine operating on a cycle.

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