Topic: Thermodynamics
Examine the following statements: (i) Work is high grade energy. (ii) It is possible for a heat engine to produce work in a cycle by exchanging heat with bodies at same temperature. (iii) It is impossible to construct a device which operating in a cycle will produce no other effect other than transfer of heat from a cooler to a hotter body.
- A. All statements are wrong
- B. All statements are correct
- C. Statements (i) and (iii) are correct
- D. Statements (ii) and (iii) are correct
Answer: C. Statements (i) and (iii) are correct
Explanation: Statement (i) is true; work is fully convertible to heat, making it high-grade energy. Statement (ii) is false according to the Kelvin-Planck statement, which requires interaction with at least two thermal reservoirs at different temperatures. Statement (iii) is the Clausius statement of the Second Law of Thermodynamics, which is true.