Decreases
Increases linearly
Increases exponentially
Remains constant
✅ The correct answer is option B.
Fluid Mechanics MCQs
482. A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun’s equation for the above fluid-particle system (in SI units) is given below : Δ P/L = 375 x 10³ VOM + 10.94 x 10⁶ V²OM (SI units) If water is to be used as the fluidising medium, the minimum fluidisation velocity, VOM is
12 mm/s
16 mm/s
24 mm/s
28 mm/s
✅ The correct answer is option B.
483. With increase in the shear rate, the apparent viscosity of pseudoplastic fluids
Increases
Decreases
Remains same
May increase or decrease; depends on the magnitude of shear rate
✅ The correct answer is option B.
484. Which of the following is dimensionless?
Angular velocity
Fanning friction factor
Specific volume
None of these
✅ The correct answer is option B.
485. The most suitable flow measuring device for the fluid flow measurement in a very large diameter pipeline is a
Weir
Pitot tube
Kennison nozzle
V-notch
✅ The correct answer is option B.
486. Maintenance cost of a __________ pump for a particular duty is the least.
Centrifugal
Reciprocating
Volute
Gear
✅ The correct answer is option A.
487. Gradually varied flow in open channel is a/an __________ flow.
Steady uniform
Steady non-uniform
Unsteady uniform
Unsteady non-uniform
✅ The correct answer is option B.
488. At high Reynolds number
Inertial forces control and viscous forces are unimportant
Viscous forces predominate
Inertial forces are unimportant and viscous forces control
None of these
✅ The correct answer is option A.
489. The head loss in turbulent flow in pipe is proportional to(where, V = velocity of fluid through the pipe)
V²
1/V²
1/V
V
✅ The correct answer is option A.
490. An ideal fluid is
Frictionless & incompressible
One, which obeys Newton’s law of viscosity
Highly viscous
None of these
✅ The correct answer is option A.