MCQ
Coefficient of performance for heat pump is (when heat supplied by system is Q1):
  • A
    $\alpha=\frac{\text{Q}_2}{\text{W}}$
  • B
    $\alpha=\frac{\text{Q}_1}{\text{W}}$
  • C
    $\alpha=\frac{\text{Q}_1}{\text{Q}_2}$
  • D
    $\alpha=\frac{\text{Q}_2}{\text{Q}_1}$

Answer

  1. $\alpha=\frac{\text{Q}_2}{\text{W}}$

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Match the columns

  Column $-I$
    $R/H_{max}$
  Column $-II$
  Angle of projection $\theta $
   $A.$ $1$    $1.$ ${60^o}$
   $B.$ $4$    $2.$ ${30^o}$
   $C.$ $4\sqrt 3$    $3.$ ${45^o}$
   $D.$ $\frac {4}{\sqrt 3}$    $4.$ $tan^{-1}\,4\,=\,{76^o}$