Practice Pakistan's most useful MCQs for competitive exams

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

Answer

Submitted By :Ali Uppal

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

Answer

Submitted By :Ali Uppal

The excess of the sum of pressure & velocity heads over the vapor pressure of the liquid at the suction is called the___________________?

• (A)  Static submergence
• (B)  Net positive suction head (NPSH)
• (C)  Cavitation sensitivity
• (D)  Priming

Answer

Submitted By :Ali Uppal

A centrifugal pump is called a turbine pump, if it is having a_________________?

• (A)  Turbine type impeller
• (B)  Vaned diffusion casing
• (C)  Rotating vaned volute
• (D)  None of these

Answer

Submitted By :Ali Uppal

In centrifugal pump operation, the cavitation can be eliminated by maintaining suction pressure ______________ the vapor pressure of the liquid at the suction temperature?

• (A)  Lower than
• (B)  Higher than
• (C)  Equal to
• (D)  None of these

Answer

Submitted By :Ali Uppal

A mercury (specific gravity = 13.6) manometer connected across an orificemeter fitted in a pipe shows a manometer reading of 2 cms. If the manometer liquid is changed to carbon tetrachloride (specific gravity = 1.6), then for the same flow rate of water the new manometer reading will be _______________ cms?

• (A)  17
• (B)  42
• (C)  84
• (D)  1.8

Answer

Submitted By :Ali Uppal

Power required for mixing Newtonian fluids is a function of the _________________?

• (A)  Speed of impeller, diameter of impeller & viscosity
• (B)  Density & viscosity of fluid only
• (C)  Density of fluid, viscosity of fluid & impeller dia only
• (D)  None of these

Answer

Submitted By :Ali Uppal

Which of the following properties of a fluid is responsible for offering resistance to shear ?

• (A)  Surface tension
• (B)  Viscosity
• (C)  Specific gravity
• (D)  All

Answer

Submitted By :Ali Uppal

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

Answer

Submitted By :Ali Uppal

The Mach number for hypersonic flow of compressible fluid is____________________?

• (A)  1
• (B)  > 1
• (C)  > 4
• (D)  < 2

Answer

Submitted By :Ali Uppal