MCQ
Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason $R$. Assertion A : Efficiency of a reversible heat engine will be highest at $-273^{\circ} C$ temperature of cold reservoir.

Reason $R$ : The efficiency of Carnot's engine depends not only on temperature of cold reservoir but it depends on the temperature of hot reservoir too and is given as $\eta=\left(1-\frac{ T _2}{ T _1}\right)$.

In the light of the above statements, choose the correct answer from the options given below

  • A
    $A$ is true but $R$ is false
  • B
    Both $A$ and $R$ are true but $R$ is NOT the correct explanation of $A$
  • C
    $A$ is false but $R$ is true
  • Both $A$ and $R$ are true and $R$ is the correct explanation of $A$

Answer

Correct option: D.
Both $A$ and $R$ are true and $R$ is the correct explanation of $A$
d
Both $A$ and $R$ are true and $R$ is the correct explanation of $A$

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