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

Related Mcqs:

1. 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

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

   A. Directly as square of gas density
   B. Directly as gas density
   C. Directly as square root of gas density
   D. Inversely as gas density

3. The fluid velocity varies as the square root of the cylindrical pipe diameter in case of steady state laminar flow at constant pressure drop of _____________ fluid?

   A. Dilatent
   B. Pseudo-plastic
   C. Bingham plastic
   D. Newtonian

4. 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.

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

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

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 power consumed now will be _____________ hp?

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

7. The fluid velocity varies as the square of the cylindrical pipe diameter, in case of steady state laminar flow at constant pressure drop, for ______________ fluid?

   A. Newtonian
   B. Dilatant
   C. Pseudo-plastic

   D. Non-Newtonian

8. The fluid velocity varies as the cube of the cylindrical pipe diameter in case of steady state laminar flow at constant pressure drop for ____________ fluid?

   A. Newtonian
   B. Pseudo-plastic
   C. Dilatent
   D. Bingham plastic

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. In Newton’s law range, the terminal velocity of a solid spherical particle falling through a stationary fluid mass varies as the ______________ of its diameter?

    A. Inverse
    B. Square root
    C. Second power
    D. First power