141. Navier-Stokes equation is useful in the analysis of __________ fluid flow problems.
Non-viscous
Viscous
Turbulent
Rotational
✅ The correct answer is option B.
Fluid Mechanics MCQs
142. In continuous fluidisation
Solids are completely entrained
The pressure drop is less than that for batch fluidisation
There is no entrainment of solids
Velocity of the fluid is very small
✅ The correct answer is option A.
143. Check in a centrifugal pump is
Provided in the discharge line
Generally a globe valve
Provided to prevent liquid from backing up through the pump when the pump is turned off or accidently stops running
All of the above
✅ The correct answer is option D.
144. A bed consists of particles of density 2000 kg/m³. If the height of the bed is 1.5 metres and its porosity 0.6, the pressure drop required to fluidise the bed by air is
25.61 kPa
11.77 kPa
14.86 kPa
21.13 kPa
✅ The correct answer is option B.
145. The Mach number for hypersonic flow of compressible fluid is
1
> 1
> 4
< 2
✅ The correct answer is option C.
146. With increase in the ratio of orifice diameter to pipe diameter, the fraction of the orifice pressure differential that is permanently lost
Increases
Decreases
Remains unchanged
Increases exponentially
✅ The correct answer is option B.
147. When the water is warm, the height to which it can be lifted by a pump
Decreases due to reduced viscosity
Decreases due to reduced vapour pressure
Increases due to increased vapour pressure
Decreases due to increased frictional resistance
✅ The correct answer is option B.
148. Cocks are used to control
Water
Any liquid
Solids
None of these
✅ The correct answer is option B.
149. The normal stress is the same in all directions at a point in a fluid, when the fluid is
Non-viscous
Incompressible
Both A and B
Having no motion of one fluid layer relative to the other
✅ The correct answer is option D.
150. Water hammer is caused, when water flowing in a pipe is suddenly brought to rest by closing the valve. The extent of pressure thus produced due to water hammer depends on the
Pipe length
Fluid velocity in the pipe
Time taken to close the valve
All of the above
✅ The correct answer is option D.