31. Turbulent flow generally occurs for cases involving
Highly viscous fluid
Very narrow passages
Very slow motion
None of these
✅ The correct answer is option D.
Fluid Mechanics MCQs
32. In a fully turbulent flow (Re > 105) in a pipe of diameter ‘d’, for a constant pressure gradient, the dependence of volumetric flow rate of an incompressible fluid is
d
d2
d2.5
d4
✅ The correct answer is option C.
33. The line of action of the buoyant force passes through the centre of gravity of the
Submerged body
Displaced volume of the fluid
Volume of fluid vertically above the body
Horizontal projection of the body
✅ The correct answer is option B.
34. The fluid in which the shearing stress within it is proportional to the velocity gradient across the sheared section, is called a __________ fluid.
Bingham
Newtonion
Perfect
None of these
✅ The correct answer is option B.
35. A double acting reciprocating pump compared to a single acting pump (of almost same size working under same pressure levels) would give almost double
Head
Discharge
Efficiency
None of these
✅ The correct answer is option B.
36. The fluid velocity varies as the square of the cylindrical pipe diameter, in case of steady state laminar flow at constant pressure drop, for __________ fluid.
Newtonion
Dilatant
Pseudoplastic
Non-Newtonion
✅ The correct answer is option A.
37. Minimum porosity for fluidisation is
That corresponding to static bed
That corresponding to completely fluidised bed
The porosity of the bed when true fluidisation begins
Less than that of the’ static bed
✅ The correct answer is option C.
38. Cavitation in a pump creates so many undesirable effects. Out of the following, which is not an undesirable effect created by cavitation?
Decrease in effect
Increase in thrust
Develops noise
Develops high pressure
✅ The correct answer is option D.
39. The rate of change of moment of momentum represents the __________ by the fluid.
Torque applied
Force exerted
Work done
Power developed
✅ The correct answer is option A.
40. For laminar flow of a shear thinning liquid in a pipe, if the volumetric flow rate is doubled, the pressure gradient will increase by a factor of
2
<2
>2
1-Feb
✅ The correct answer is option A.