650 Important Hydraulics And Fluid Mechanics MCQ Question and Answer | PDF Free Download
1.The working of which of the following hydraulic units is based on Pascal's law?
- AAir lift pump
- BJet pump
- CHydraulic coupling
- DHydraulic press
2.The angle of taper on draft tube is
- AGreater than 15°
- BGreater than 8°
- CGreater than 5°
- DLess than 8°
3.A glass tube of smaller diameter is used while performing an experiment for the capillary rise of water because
- AIt is easier to see through the glass tube
- BGlass tube is cheaper than a metallic tube
- CIt is not possible to conduct this experiment with any other tube
- DAll of the above
4.The product of mass and acceleration of flowing liquid is called
- AInertia force
- BViscous force
- CGravity force
- DPressure force
5.The property by virtue of which a liquid opposes relative motion between its different layers is called
- ASurface tension
- BCoefficient of viscosity
- CViscosity
- DOsmosis
6.When a body is placed over a liquid, it will float if
- AGravitational force is equal to the up-thrust of the liquid
- BGravitational force is less than the up-thrust of the liquid
- CGravitational force is more than the up-thrust of the liquid
- DNone of the above
7.If a body floating in a liquid returns back to its original position, when given a small angular displacement, the body is said to be in
- ANeutral equilibrium
- BStable equilibrium
- CUnstable equilibrium
- DNone of these
8.To avoid vaporisation in the pipe line, the pipe line over the ridge is laid such that it is not more than
- A2.4 m above the hydraulic gradient
- B6.4 m above the hydraulic gradient
- C10.0 m above the hydraulic gradient
- D5.0 above the hydraulic gradient
9.The optimum value of vane exit angle for a centrifugal pump impeller is
- A10-15°
- B20-25°
- C30-40°
- D50-60°
10.Air vessels in reciprocating pump are used to
- ASmoothen flow
- BReduce acceleration to minimum
- CIncrease pump efficiency
- DSave pump from cavitations
11.The normal stress is same in all directions at a point in a fluid
- AOnly when the fluid is frictionless
- BOnly when the fluid is incompressible and has zero viscosity
- CWhen there is no motion of one fluid layer relative to an adjacent layer
- DIrrespective of the motion of one fluid layer relative to an adjacent layer
12.A double overhung Pelton wheel has
- ATwo jets
- BTwo runners
- CFour jets
- DFour runners
13.The viscosity of water at 20°C is
- AOne stoke
- BOne centistokes
- COne poise
- DOne centipoises
14.The kinematic viscosity is the
- ARatio of absolute viscosity to the density of the liquid
- BRatio of density of the liquid to the absolute viscosity
- CProduct of absolute viscosity and density of the liquid
- DProduct of absolute viscosity and mass of the liquid
15.Which of the following pump is successfully used for lifting water to the turbines?
- ACentrifugal pump
- BReciprocating pump
- CJet pump
- DAir lift pump
16.The centrifugal pump preferred for a specific speed between 80 to 160 r.p.m. is
- ASlow speed with radial flow at outlet
- BMedium speed with radial flow at outlet
- CHigh speed with radial flow at outlet
- DHigh speed with mixed flow at outlet
17.The efficiency of jet propulsion for a ship with inlet orifices at right angles to the direction of motion of ship is given by
- A[2(Vr - v) v]/ Vr²
- B[2(Vr + v) v]/ Vr²
- C[(Vr - v) v]/ Vr
- D[(Vr + v) v]/ Vr
18.In an inward flow reaction turbine
- AThe water flows parallel to the axis of the wheel
- BThe water enters at the center of the wheel and then flows towards the outer periphery of the wheel
- CThe water enters the wheel at the outer periphery and then flows towards the center of the wheel
- DThe flow of water is partly radial and partly axial
19.In an outward flow reaction turbine
- AThe water flows parallel to the axis of the wheel
- BThe water enters at the centre of the wheel and then flows towards the outer periphery of the wheel
- CThe water enters the wheel at the outer periphery and then flows towards the centre of the wheel
- DThe flow of water is partly radial and partly axial
20.The specific speed (Ns) of a centrifugal pump is given by
- A(N√Q)/H2/3
- B(N√Q)/H3/4
- C(N√Q)/H
- D(N√Q)/H5/4