# Practice Test: Question Set - 23

**1. Co-efficient of discharge (**

*C*) is defined as actual discharge/theoretical discharge and is equal to_{d}*C*._{c}*C*; where_{v}*C*= Co-efficient of contraction and_{c}*C*= co-efficient of velocity._{v}*C*of an orifice is usually about_{d}- (A) 0.42

- (B) 0.62

- (C) 0.82

- (D) 0.98

**2. Mach number is important in a fluid flow problem, when the inertia and __________ forces predominate.**

- (A) Elastic

- (B) Viscous

- (C) Gravity

- (D) None of these

**3. The head loss in turbulent flow in a pipe varies**

- (A) As velocity

- (B) As (velocity)

^{2}

- (C) Inversely as the square of diameter

- (D) Inversely as the velocity

**4. Boundary layer thickness in turbulent flow over a flat plate increases as(where,**

*d*= distance from the leading edge.)- (A) √

*d*

- (B)

*d*

^{2/3}

- (C)

*d*

^{4/5}

- (D)

*d*

^{1/3}

**5. The fluid property, due to which, mercury does not wet the glass is**

- (A) Surface tension

- (B) Viscosity

- (C) Cohesion

- (D) Adhesion

**6. 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

**7. The ratio of inertial forces to elastic forces is called the __________ number.**

- (A) Reynolds

- (B) Mach

- (C) Euler

- (D) Weber

**8. Select the correct statement.**

- (A) The discharge through a Venturimeter depends
upon Δp only and is independent of orientation of the meter

- (B) A Venturimeter with a given gage difference discharges at a greater
rate, when the flow is vertically downward through it, than when the flow is
vertically upward

- (C) For a given pressure difference, the discharge of gas is greater
through a Venturimeter, when compressibility is taken into account, than when
it is neglected

- (D) The overall pressure loss is the same in a given pipe line, whether
a Venturimeter or a nozzle with the same throat dia is used

**9. Centrifugal compressors compared to reciprocating compressors**

- (A) Require less space

- (B) Have quieter operation

- (C) Have lower operating costs

- (D) All (a), (b) and (c)

**10. Nominal size of the discharge pipe of a pump is usually __________ the nominal size of the inlet pipe.**

- (A) Smaller than

- (B) Larger than

- (C) Same as

- (D) Twice

**11. A fluid element has a velocity**

*V*= -*y*^{2}.*xi*+ 2*yx*^{2}.*j*. The motion at (*x*,*y*) = (1/√2, 1) is- (A) Rotational and incompressible

- (B) Rotational and compressible

- (C) Irrotational and compressible

- (D) Irrotational and incompressible

**12. Which of the following has the minimum compressibility?**

- (A) Water at room temperature

- (B) Air at room temperature

- (C) Oxygen at room temperature

- (D) Nitrogen at room temperature

**13. A stream tube is that, which has __________ cross-section entirely bounded by stream lines.**

- (A) A circular

- (B) Any convenient

- (C) A small

- (D) A large

**14. Power loss in an orificemeter is __________ that in a Venturimeter.**

- (A) Less than

- (B) Same as

- (C) More than

- (D) Data insufficient, cannot be predicted

**15. Applying a pressure drop across a capillary results in a volumetric flow rate '**

*Q*' under laminar flow conditions. The flow rate for the same pressure drop, in a capillary of the same length but half the radius is- (A)

*Q*/2

- (B)

*Q*/4

- (C)

*Q*/8

- (D)

*Q*/16

**View All Answers**

**Next Tests:**