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This question has Statement 1 and Statement 2. Of the four choices given after the Statements, choose the one that best describes the two Statements. Statement 1: An inventor claims to have constructed an engine that has an efficiency of 30 % when operated between the boiling and freezing points of water. This is not possible. Statement 2: The efficiency of a real engine is always less than the efficiency of a Carnot

Options

  1. AStatement 1 is true, Statement 2 is true, Statement 2 is not the correct explanation of Statement 1.
  2. BStatement 1 is true, Statement 2 is false.
  3. CStatement 1 is false, Statement 2 is true.
  4. DStatement 1 is true, Statement 2 is true, Statement 2 is the correct explanation of Statement 1.

Correct answer

D. Statement 1 is true, Statement 2 is true, Statement 2 is the correct explanation of Statement 1.

Step-by-step solution

According to Carnot's theorem - no heat engine working between two given temperatures of source and sink can be more efficient than a perfectly reversible engine i.e. Carnot engine working between the same two temperatures. Efficiency of Carnot's engine, n=1- T₂ T₁ where, T₁= temperature of source T₂= temperature of sink

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