For minimum work input in a two stage compression process the intermediated pressure is the A. Arithmetic process of suction and discharge pressure B. Logarithmic mean of suction and discharge pressure C. Geometric mean of suction and discharge pressure D. Hyperbolic mean of suction and discharge

For minimum work input in a two stage compression process the intermediated pressure is the A. Arithmetic process of suction and discharge pressure B. Logarithmic mean of suction and discharge pressure C. Geometric mean of suction and discharge pressure D. Hyperbolic mean of suction and discharge  
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Adiabatic compression is one in which A. Temperature during compression remains constant B. No heat leaves or enters the compressor cylinder during compression C. Temperature rise follows a linear relationship D. Work done is maximum.

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The net positive suction head (NPSH) of a centrifugal pump is defined as the sum of the velocity head and the pressure head at the (A) Discharge (B) Suction (C) Suction minus vapor pressure of the liquid at suction temperature (D) Discharge minus vapor pressure of the liquid at the discharge temperature

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