In case of a, centrifugal pump, the ratio h1/h2 is termed as the _____________ efficiency (where, h1 = actual measured head & h2 = head imparted to the fluid by impeller)?

Related Mcqs:

1. If the head is doubled in & centrifugal pump, the power required will increase in the ratio of__________________?

   A. 23
   B. 23/2
   C. 25/2
   D. 21/3

2. A fluid is termed as the Newtonian fluid, when the shear stress is _________________ the velocity gradient ?

   A. Independent of
   B. Inversely proportional to
   C. Directly proportional to
   D. None of these

3. Good design of the casing of a centrifugal pump aims at minimising the __________________________?

   A. Cavitation
   B. Frictional losses
   C. Kinetic energy loss
   D. Static head

4. In a counter flow heat exchanger, hot fluid enters at 170°C & leaves at 150°C, while the cold fluid enters at 50°C & leaves at 70°C. The arithmetic mean temperature difference in this case is ______________ °C?

   A. 20
   B. 60
   C. 120
   D. ∞

5. The type of pump used for lifting large quantity of sewage is a _________________ pump ?

   A. Gear
   B. Centrifugal
   C. Reciprocating
   D. Plunger

6. The efficiency of a Carnot heat engine operating between absolute temperatures T1 and T2 (when, T1 > T2) is given by (T1 – T2)/T1. The co-efficient of performance (CO.P.) of a Carnot heat pump operating between T1 and T2 is given by_________________?

   A. T1/(T1-T2)
   B. T2/(T1-T2)
   C. T1/T2
   D. T2/T1

7. Gage pressure within a spherical droplet of a fluid is ‘p’. What will be gage pressure within a bubble of the same size & of the same fluid ?

   A. p
   B. 2 p
   C. 0.5 p
   D. 0.25 p

8. Reynolds number of a fluid flowing in a circular pipe is 10,000. What will be the Reynolds number when the fluid velocity is decreased by 30% & the pipe diameter is increased by 30% ?

   A. 9,100
   B. 13,000
   C. 7,000
   D. 2,550

9. With increase in compression ratio, the volumetric efficiency of air compressor____________________?

   A. Increases
   B. Decreases
   C. Remain same
   D. May increase or decrease (depends on the suction pressure)

10. For the Stoke’s law to be valid in the case of a falling sphere in a fluid, the_____________________?

    A. Reynolds number (based on sphere diameter) should be < 1
    B. Flow around the sphere should be in turbulent region
    C. Sphere must be metallic
    D. Fluid density should be constant