## Hydraulics MCQ Practice Questions (Civil Engineering) Set 4

Options are :

• B
• C
• A
• D

##### Pick up the incorrect statement from the following:

Options are :

• In radial flow, fluid flows such that pressure and velocity at any point change with respect to its distance from the central axis
• In radial flow, flow may take place radially inward to or outward from the centre
• In radial flow, flow is one dimensional with stream lines parallel
• In radial flow, velocity of flow is in a radial direction

Answer :In radial flow, flow is one dimensional with stream lines parallel

##### The most efficient channel section, is:

Options are :

• Triangular
• Half hexagon in the form of trapezoid
• Semi-circular
• Rectangular

Answer :Half hexagon in the form of trapezoid

Options are :

• 2.6 cm
• 2.5 cm
• 2.4 cm
• 2.7 cm

##### Pick up the correct statement from the following:

Options are :

• In uniform flow, the velocity of a fluid does not change with respect to length of flow direction
• In incompressible flow the density of a fluid remains constant
• All the above
• In compressible flow, the density of a fluid changes from point to point

##### Frictional loss of head includes the loss of energy due to:

Options are :

• Both A and B
• Turbulence
• None of these
• Viscosity

##### To measure very low pressure, we use:

Options are :

• Barometers
• Manometers
• Differential manometers
• Piezometers

##### A triangular notch is preferred to a rectangular notch because:

Options are :

• All the above
• It gives more accurate results for low discharge
• Only one reading is required
• It measures a wide range of flows accurately
• Its formula is simple to remember

##### Pick up the correct statement regarding convergent divergent mouth piece from the following:

Options are :

• All the above
• It converges upto Venacontracta and then diverges
• In this mouth piece there is no loss of energy due to sudden enlargement
• The coefficient of discharge is unity

##### Equation of continuity of fluids is applicable only if:

Options are :

• Flow is compressive
• Velocity is uniform over the cross-sections
• All the above
• Flow is one dimensional

Options are :

• D
• B
• C
• A

Options are :

• 6 cm
• ?2 cm
• 4 cm
• 2?3 cm

Options are :

• 10° 20'
• 10° 5'
• 10° 10'
• 10° 15'

Options are :

• 9.81 kg wt
• 1 kg wt
• 9.81 kg mass
• 0.98 kg wt

Options are :

• 1.0
• 2.5
• 0.5
• 2.0
• 1.5

##### Discharge through a totally submerged orifice, is directly proportional to:

Options are :

• None of these
• Reciprocal of the area of the opening
• Square root of the opening
• Square root of the difference in elevation of water surface
• Difference in elevation of water surfaces

Answer :Square root of the difference in elevation of water surface

Options are :

• D
• A
• B
• C

##### Falling drops of water become spheres due to:

Options are :

• Viscosity
• Surface tension
• Cohesion

Options are :

• 0.5 H
• 0.2 H
• 0.1 H
• 0.3 H
• 0.4 H

##### The line joining the points to which the liquid rises in vertical piezometer tubes fitted at different cross-sections of a conduit, is known as:

Options are :

• Piezometric line
• All the above

##### The shape of fire hose nozzle is generally kept:

Options are :

• Cylindrical
• Convergent divergent
• Divergent
• Convergent

##### Pick up the correct statement from the following:

Options are :

• For maximum velocity of flow, the depth of water in the circular channel must be 0.81 times the diameter of the channel
• All the above
• For maximum discharge the depth of flow must be 0.95 times the diameter of circular channel
• For maximum velocity, the hydraulic mean depth must be 0.3 times the diameter of circular channel

Options are :

• C
• D
• B
• A

##### The length of hydraulic jump is roughly:

Options are :

• 5 to 7 times its height
• 2 to 3 times its height
• None of these
• 3 to 5 times its height

Answer :5 to 7 times its height

##### For uniform flow in canals:

Options are :

• There is a balance between the frictional loss and drop in elevation of the channel
• All the above
• Bed of channel represents the hydraulic gradient
• Bed and free water surfaces of a channel are parallel to each other

Options are :

• 8% to 10%
• 6% to 7%
• 30% to 40%
• 25% to 30%
• 18% to 20%

##### If H is the difference of liquid levels on two sides of an orifice (width b, depth d), the discharge through the orifice will be:

Options are :

• Cdbd^(2)?2gH
• Cdbd.2g H^(1/2)
• Cdbd?2gh
• Cdb^(2)d?2gH

##### For solving the problems is hydraulic engineering, the velocity used is:

Options are :

• None of these
• Mean of the velocities at the centre and that along the pipe surface
• Velocity at the centre of pipe section
• Average velocity of flow over a section

Answer :Average velocity of flow over a section

##### The metacentric height of a body equals the distance between:

Options are :

• The centre of buoyancy and metacentre
• None of these
• The metacentre and centre of gravity
• The centre of gravity and centre of buoyancy

Answer :The metacentre and centre of gravity

##### For steady flow in open channels, which one of the following does not change:

Options are :

• Velocity of flow
• Rate of flow
• Depth of flow
• All of these