For a specific centrifugal air blower operating at constant speed & capacity, the power requirement and pressure vary_______________?

Related Mcqs:

1. Consider a centrifugal pump having a specific impeller diameter, fixed impeller speed pumping a liquid of constant density at a particular discharge capacity. With decrease in the capacity of the pump, the _______________ decreases?

   A. NPSH required
   B. BHP required by the pump
   C. Head of the liquid pumped
   D. All A., B. and C.

2. In case of centrifugal fan or blower, the gas capacity varies as __________________?

   A. Speed
   B. (Speed)2
   C. (Speed)3
   D. (Speed)0.5

3. The pressure and power requirement of a gas fan at constant speed & capacity varies ____________ the gas density?

   A. Directly as
   B. Inversely as square root of
   C. Inversely as
   D. As square of

4. 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, the power consumed now will be _____________ hp?

   A. 0.5
   B. 2
   C. 4
   D. 1

5. Power requirement of fans having constant wheel diameter varies _____________ fan speed?

   A. As square of
   B. Directly as
   C. As cube of
   D. None of these

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, the new discharge will be __________ litres/minute ?

   A. 500
   B. 200
   C. 1000
   D. 750

7. 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

8. 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

9. At a constant speed of the centrifugal pump, it‟s _____________ the impeller diameter?

   A. Capacity varies directly with
   B. Head varies as the square of
   C. Horsepower varies as the cube of
   D. All A., B. and C.

10. Higher specific speed (200-500) of a centrifugal pump indicates that the pump is of ______________ flow type?

    A. Axial
    B. Radial
    C. Mixed
    D. None of these