The relation between efficiency $\eta$ of a heat engine and the co-efficient of performance $\alpha$ of a refrigerator is

• A

  $\eta =\frac{1}{1-\alpha }$
• Correct answer
  B

  $\eta =\frac{1}{1+\alpha }$
• C

  $\eta =1+\alpha$
• D

  $\eta =1-\alpha$

Hence, the correct answer is option: 'B'.