What is the co-efficient of contraction, if a fluid jet discharging from a 50 mm diameter orifice has a 40 mm diameter at its vena-contracta ?

Related Mcqs:

1. Cd, Cc and Cv are related (for flow through an orifice) as (where, Cd = discharge co-efficient, Cc = co-efficient of contraction = (area of jet at vena-contracta/area of opening), Cv = co-efficient of velocity = (actual velocity at vena-contracta/theoretical velocity)?

   A. Cd = Cc/Cv
   B. Cd = Cc.Cv
   C. Cd = Cv/ Cc
   D. None of these

2. The fluid jet discharging from a 2″ diameter orifice has a diameter of 1.75″ at its venacontracta. The co-efficient of contraction is___________________?

   A. 1.3
   B. 0.766
   C. 0.87
   D. None of these

3. The actual velocity at vena-contracta for flow through an orifice from a reservoir is given by_____________________?

   A. Cv . √(2gH)
   B. Cc . √(2gH)
   C. Cd . √(2gH)
   D. Cv . Va

4. For flow through an orifice from a reservoir, the actual velocity at the vena contracta is given by _________________?

   A. √(2gh)
   B. C.V. √(2gh)
   C. Cd √(2gh)
   D. Cc √(2gh)

5. Co-efficient of discharge (Cd) is defined as actual discharge/theoretical discharge and is equal to Cc . Cv; where Cc = Co-efficient of contraction and Cv = co-efficient of velocity. Cd of an orifice is usually about__________________?

   A. 0.42
   B. 0.62
   C. 0.82
   D. 0.98

6. With increase in the ratio of orifice diameter to pipe diameter, the fraction of the orifice pressure differential that is permanently lost________________?

   A. Increases
   B. Decreases
   C. Remains unchanged
   D. Increases exponentially

7. Vena-contracta pressure tapping is at a distance _______________ from the position of an orificemeter fitted in a pipe of internal diameter ‘d’ ?

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

8. Bernoulli’s equation for fluid flow is derived following certain assumptions. Out of the assumptions listed below, which set of assumptions is used in derivation of Bernoulli’s equation? A. Fluid flow is frictionless & irrotational. B. Fluid flow is steady. C. Fluid flow is uniform & turbulent. D. Fluid is compressible. E. Fluid is incompressible ?

   A. A, C, D
   B. B, D, E
   C. A, B, E
   D. A, D, E

9. Vena-contracta formed during flow of a liquid through an orificemeter has__________________?

   A. Minimum liquid cross-section
   B. More diameter compared to orifice diameter
   C. Minimum velocity of fluid stream
   D. None of these

10. Location of vena-contracta in an orificemeter does not depend upon the________________?

    A. Type of orifice
    B. Density, viscosity & compressibility of the fluid
    C. Ratio of pipe diameter to orifice diameter
    D. Pipe roughness