Practice Pakistan's most useful MCQs for competitive exams

At low Reynolds number______________?

• (A)  Viscous forces are unimportant
• (B)  Viscous forces control
• (C)  Viscous forces control and inertial forces are unimportant
• (D)  Gravity forces control

Answer

Submitted By :Ali Uppal

Which of the following valves will incur maximum pressure drop for the same discharge of water ?

• (A)  Globe valve
• (B)  Gate valve
• (C)  Needle valve
• (D)  Butterfly valve

Answer

Submitted By :Ali Uppal

Venturimeter and orificemeter measures the _____________ of the fluid?

• (A)  Pressure
• (B)  Maximum velocity
• (C)  Average velocity
• (D)  Point velocity

Answer

Submitted By :Ali Uppal

A fluid which has a linear relationship between the magnitude of applied shear-stress and the resulting rate of deformation is called a/an _____________ fluid?

• (A)  Newtonian
• (B)  Non-Newtonian
• (C)  Ideal
• (D)  Incompressible

Answer

Submitted By :Ali Uppal

A pipe has a porous section of length L as shown in the figure. Velocity at the start of this section of V0. If fluid leaks into the pipe through the porous section at a volumetric rate per unit area q(x/L)2, what will be axial velocity in the pipe at any „x‟? Assume incompressible one dimensional flow i.e., no gradients in the radial direction ?

• (A)  VX = V0 + q (x3/L2D)
• (B)  VX = V0 + ⅓q (x3/L2)
• (C)  VX = V0 + 2q (x2/LD)
• (D)  VX = V0 + (4/3) q (x3/L2D)

Answer

Submitted By :Ali Uppal

Navier-Stokes equation is useful in the analysis of _____________ fluid flow problems?

• (A)  Non-viscous
• (B)  Viscous
• (C)  Turbulent
• (D)  Rotational

Answer

Submitted By :Ali Uppal

The head loss in turbulent flow in a pipe varies_________________?

• (A)  Directly as the velocity
• (B)  Inversely as the square of the velocity
• (C)  Approximately as the square of the velocity
• (D)  Inversely as the square of the diameter

Answer

Submitted By :Ali Uppal

Pressure difference between two points in vessels, pipelines or in two different pipelines can be measured by a differential manometer. The pressure difference measured as the mm of water column in case of mercury-water, differential manometer is equal to (where, H = difference in height of mercury column in mm)?

• (A)  H
• (B)  12.6 H
• (C)  13.6 H
• (D)  14.6 H

Answer

Submitted By :Ali Uppal

Which of the following produces maximum pressure difference for transportation of gases ?

• (A)  Vacuum pumps
• (B)  Blowers
• (C)  Fans
• (D)  Compressors

Answer

Submitted By :Ali Uppal

Bernoulli’s equation is dependent on the__________________?

• (A)  First law of thermodynamics
• (B)  Third law of thermodynamics
• (C)  Law of conservation of momentum
• (D)  None of these

Answer

Submitted By :Ali Uppal