A. Fanning friction factor is inversely proportional to Reynolds number always
B. The property of a randomly packed bed (with raschig rings) is given by the ratio of the total
volume to the volume of voids in the bed
C. Mach number in an incompressible fluid is always unity
D. Mach number is given by the ratio of the speed of the fluid to that of sound in the fluid under
conditions of flow
Related Mcqs:
- Pick out the correct statement pertaining to transition/ entrance length in fluid flow ?
A. The length of entrance region of pipe, in which full development of fluid flow takes place
such that velocity profile does not change downstream, is called the transition length
B. Transition length for laminar flow of Newtonian fluids in a pipe of diameter ‘d’ is equal to
0.05. D.NRe
C. Transition length for turbulent flow of Newtonian fluids in a smooth pipe of diameter ‘d’ is
equal to 50 D
D. All A., B. and C. - Pick out the correct statement pertaining to Venturimeter ?
A. A Venturimeter with a fixed pressure drop discharges more, when the flow is vertically
downward, than when the flow is vertically upward
B. The co-efficient of contraction of a Venturimeter is always unity
C. For a fixed pressure drop, the discharge of a gas through a Venturimeter is greater, when
compressibility is taken into account, than when it is neglected
D. None of these - Consider two pipes of same length and diameter through which water is passed at the same velocity. The friction factor for rough pipe is f1 and that for smooth pipe is f2. Pick out the correct statement ?
A. f1 = f2
B. f1 < f2
C. f1 > f2
D. Data not sufficient to relate f1 & f2 - Pick out the correct statement?
A. Human blood is a Newtonian fluid
B. A Newtonian fluid obeys Newton’s law of cooling
C. For a non-Newtonian fluid, a straight line passes through the origin in a plot between shear
stress and shear gradient
D. Thin lubricating oil is an example of a non-Newtonian fluid - Pick out the correct statement?
A. A forced vortex occurs when fluid rotates as a solid about an axis
B. In laminar flow, Newton’s law of viscosity does not apply
C. A free vortex occurs, when fluid rotates as a solid
D. In turbulent flow, there are neither cross-currents nor eddies - Pick out the correct statement pertaining to the flow through a converging-diverging tube ?
A. The value of Mach number is always unity at the throat
B. No shock wave develops in the tube when the Mach number at exit is greater than unity
C. Throughout the converging portion of the tube, the density increases in the downstream
direction
D. None of these - Pick out the wrong statement?
A. Greater is the kinematic viscosity of the liquid, greater is the thickness of the boundary layer
B. Blowers develop a maximum pressure of 2 atmospheres
C. Friction losses in pipe fittings are generally expressed in terms of velocity heads
D. Fanning friction factor in case of turbulent flow of liquids in pipe depends upon relative
roughness & Reynolds number - Pick out the wrong statement ?
A. Momentum transfer in laminar flow results from velocity gradient
B. A fluid in equilibrium is not free from shear stress
C. The viscosity of a non-Newtonian fluid is a function of temperature only
D. Both B. and C. - Pick out the wrong statement?
A. The shear stress at the pipe (dia = D, length = L) wall in case of laminar flow of Newtonian fluids is (D/4L). Δp
B. In the equation, T. gc = k. (du/dy)n the value of ‘n’ for pseudoplastic and Dilatant fluid are 1 respectively
C. Shear stress for Newtonian fluid is proportional to the rate of shear in the direction perpendicular to motion
D. With increase in the Mach number >0.6, the drag co-efficient decreases in case of compressible fluids - Pick out the wrong statement about cavitation?
A. Sudden reduction of pressure in a fluid flow system caused by flow separation, vortex formation or abrupt closing of valve leads to cavitation
B. Cavitation may be caused due to boiling of liquid by decreasing the pressure resulting in
formation & collapse of vapor cavities
C. Cavitation begins at higher static pressure and lower velocity in larger diameter pipelines
resulting in audible noise
D. Large scale cavitation cannot damage pipeline, restrict fluid flow and damage steam turbine
blades
