With increase in molecular weight of the gas, the head developed by a centrifugal compressor will________________?

Related Mcqs:

1. The variable required to be known in correlations used for estimating the horse power of a centrifugal gas compressor and hence its cost is P. Inlet pressure Q. Compressor rpm R. Delivery pressure S. Volumetric flow rate at inlet ?

   A. P, Q and R
   B. P and R
   C. R and S
   D. P, Rand S

2. Horsepower increase of a centrifugal gas compressor without altering the volumetric flow rate will _____________ the gas discharge pressure?

   A. Increase
   B. Decrease
   C. Not change
   D. Exponentially decrease

3. 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

4. Liquid delivery by centrifugal pump starts, only when the head developed by it is equal to the ____________ head?

   A. Manometric
   B. Total
   C. Static
   D. Friction

5. In case of isentropic flow, the speed of sound in an ideal gas is proportional to (where M = molecular weight of the gas) ?

   A. 1/√M
   B. √M
   C. 1/M
   D. M

6. A centrifugal pump has the following specifications: Power = 4 H.P.; Speed = 800 rpm Head = 8 metres Flow = 1000 litres/minutes. If its speed is halved, then the new head will be ______________ metres?

   A. 2
   B. 4
   C. 8
   D. 5.5

7. The head developed by a centrifugal pump is largely determined by the____________________?

   A. Power of the pump
   B. Nature of the liquid being pumped
   C. Angle of the vanes and the speed of the tip of the impeller
   D. Vapour pressure of the liquid

8. Which is the correct relationship for a centrifugal pump? (Where, D = Impeller diameter, inches H = Head developed, ft of liquid pumped N = Speed of pump, rpm) ?

   A. D = 1840 H0.5/N
   B. D = 1840 N/H0.5
   C. H = 1840 D0.5/N
   D. D = 1840 H/N

9. Head developed by a centrifugal pump depends on its___________________?

   A. Speed
   B. Impeller diameter
   C. Both A. and B.
   D. Neither A. nor B.

10. Theoretical head developed by a centrifugal pump does not depend upon the _____________ the impeller?

    A. Radius of
    B. Speed of
    C. Fluid velocity leaving
    D. None of these