Hydraulics and Fluid Mechanics Questions

• Atmospheric science – How does air pressure vary with increasing altitude above the Earth's surface?
• Floating bodies – Stability criterion using metacentre A floating body is said to be not in (stable) equilibrium if its metacentre M lies below its centre of gravity G. Do you agree with this statement?
• Open-channel flow – Manning’s discharge form According to Manning's formula, the discharge Q through an open channel can be written in terms of area A, hydraulic mean depth m (i.e., R), bed slope i, and Manning's constant M = 1/n. Which expression is correct?
• Hydrostatics – Pressure variation with depth in a liquid at rest At any point in a static liquid, the intensity of pressure is __________ to the depth measured below the free surface.
• Orifices & mouthpieces – Relative coefficient of discharge Compared to a short external (projecting) mouthpiece, the coefficient of discharge Cd for a short internal (re-entrant, Borda’s) mouthpiece is generally:
• Rheology – Shape of shear stress vs rate-of-shear curve For a non-Newtonian fluid, the graph of shear stress (tau) versus rate of shear (du/dy) is generally:
• Bernoulli principle – What stays constant under ideal assumptions? According to Bernoulli's equation for steady, incompressible, inviscid flow with no shaft work or heat transfer, which quantity remains constant along a streamline?
• Flow measurement devices – Terminology for an opening in a tank wall An opening in the side of a tank or vessel such that the tank's liquid surface is below the top edge of the opening is called a:
• Centre of pressure – Vertical plane surface in a liquid For a vertically immersed plane surface, the centre of pressure lies, relative to the surface's centre of gravity (centroid), at a position:
• Water hammer in pipelines – factors affecting magnitude The magnitude (severity) of water hammer produced by sudden valve operations in a pipeline depends primarily upon:
• Lock gates – reaction between the two leaves In a lock gate, the resultant hydrostatic pressure on the gate is P, and each gate leaf is inclined at angle α to the normal to the lock side. The reaction between the two gates equals:
• Newton’s law of viscosity – correct functional relationship Newton’s law of viscosity expresses the relationship between which two quantities?
• Fluid property – resistance to relative layer motion The property of a liquid that offers resistance to the movement of one layer over another adjacent layer is called:
• Sharp-crested (narrow-crested) weir – thumb rule for thickness In a sharp-crested weir, the thickness of the crest is kept less than half of the head of water above the crest. State whether this design guideline is correct:
• Compressible flow regimes – definition of supersonic A flow is called “supersonic” if which of the following conditions holds?
• Venturimeter installation – effect of inclination on reading When a venturimeter is installed in an inclined position, then for a given discharge the instrument will indicate __________ differential head reading (between its pressure taps):
• Terminology – specific weight (weight density) “The specific weight of a fluid is also called weight density.” Decide whether this statement is:
• Compressible fluids – variability of specific weight “The specific weight of compressible fluids does not remain constant.” Is this statement:
• Composite notches – discharge over a trapezoidal notch The discharge over a trapezoidal (Cipolletti-type) notch can be expressed as the discharge over an equivalent rectangular notch __________ the discharge over a triangular (V) notch:
• Flow Classification – Time Variation of Discharge A flow in which the quantity of liquid flowing per second (discharge) remains constant with time at a given section is called steady flow.