Explore topic-wise MCQs in Environmental Engineering.

This section includes 297 Mcqs, each offering curated multiple-choice questions to sharpen your Environmental Engineering knowledge and support exam preparation. Choose a topic below to get started.

51.

If H is height of the liquid above the sill, the effect of end contractions, according to Francis formula, is

A. 0.1 H
B. 0.2 H
C. 0.3 H
D. 0.4 H
Answer» B. 0.2 H
52.

Capillary rise of water is

A. directly proportional to surface tension
B. inversely proportional to water density
C. inversely proportional to diameter of the tube
D. All of these.
Answer» E.
53.

Practical fluids possess

A. viscosity
B. surface tension
C. compressibility
D. all the above.
Answer» E.
54.

In C.G.S. system the unit of visocity is

A. dyne
B. joule
C. poise
D. Newton
Answer» D. Newton
55.

Discharge through a totally submerged orifice, is directly proportional to

A. difference in elevation of water surfaces
B. square root of the difference in elevation of water surface
C. square root of the opening
D. reciprocal of the area of the opening
Answer» C. square root of the opening
56.

The most efficient channel section, is

A. semi-circular
B. rectangular
C. triangular
D. half hexagon in the form of trapezoid.
Answer» E.
57.

An orifice is taken as large if

A. (H2 - H1) > H
B. (H2 - H1) > H/4
C. (H2 - H1) > H/2
D. (H2 - H1) > H/3
Answer» E.
58.

Barometres are used to measure

A. pressure in water channels, pipes etc.
B. difference in pressure at two points
C. atmospheric pressure
D. very low pressure
Answer» D. very low pressure
59.

Pick up the incorrect statement from to following regarding triangular notch :

A. For measuring low discharge, it gives more accurate result
B. Only one reading (i.e. H) is required for computation of discharge
C. Ventilation is necessary
D. None of these.
Answer» D. None of these.
60.

A steady uniform flow is through

A. a long pipe at decreasing rate
B. a long pipe at constant rate
C. an expanding tube at constant rate
D. an expanding tube at increasing rate
Answer» C. an expanding tube at constant rate
61.

For the most economical trapezoidal section of a channel with regards to discharge, the required condition, is

A. half of top width = sloping side
B. hydraulic depth = half the depth
C. perpendiculars drawn from the centre of the top width on to the bottom sloping side, are all equal
D. all the above.
Answer» E.
62.

Hydraulic coefficient of an orifice means the coefficient of

A. velocity
B. contraction
C. resistance
D. all the above.
Answer» E.
63.

For exerting a pressure of 4.8 kg/cm², the depth of oil (specific gravity 0.8), should be

A. 40 cm
B. 41 cm
C. 56 cm
D. 60 cm
Answer» E.
64.

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

A. velocity at the centre of pipe section
B. average velocity of flow over a section
C. mean of the velocities at the centre and that along the pipe surface
D. none of these.
Answer» C. mean of the velocities at the centre and that along the pipe surface
65.

If the volume of a liquid weighing 3000 kg is 4 cubic metres, 0.75 is its

A. specific weight
B. specific mass
C. specific gravity
D. none of these.
Answer» D. none of these.
66.

The dimensionless parameter not applicable to flowing liquids, is

A. Reynold number
B. Weber number
C. Pressure coefficient
D. Kinematic viscosity
Answer» E.
67.

Hydraulic ram is a device

A. for lifting water without an electric motor
B. for accelerating water flow
C. for lifting heavy loads
D. none of these.
Answer» B. for accelerating water flow
68.

If v1 and v2 are the velocities of flow before and after sudden enlargement in a pipe, the head loss given by Carnot and Borda equation, is

A. (v2² - v1²)/2g
B. (v1 - v2)²/2g
C. (v2 - v1)²/2g
D. (v1 + v2)²/2g
Answer» C. (v2 - v1)²/2g
69.

The total pressure force on a plane area is equal to the area multiplied by the intensity of pressure at its centroid, if

A. area is horizontal
B. area is vertical
C. area is inclined
D. all the above.
Answer» E.
70.

Uniform flow is said to occur when

A. size and shape of the cross-section in a particular length remain constant
B. size and shape of the cross-section change along a length
C. frictional loss in the particular length of the channel will the more than the drop in its elevation
D. frictional loss in the particular length of the channel, will be less than the drop in elevation.
Answer» B. size and shape of the cross-section change along a length
71.

Most economical section of a triangular channel, is

A. equilateral triangle
B. right angled triangle
C. isosceles triangle with 45° vertex angle
D. right angled triangle with equal sides.
Answer» E.
72.

If velocities of fluid particles vary from point to point in magnitude and direction, as well as from instant to instant, the flow is said to be

A. laminar
B. turbulent flow
C. uniform flow
D. non-uniform flow.
Answer» C. uniform flow
73.

In an open tube, free surface of mercury remains

A. horizontal
B. curved upwards
C. curved downwards
D. none of these.
Answer» D. none of these.
74.

The value of kinetic energy correction factor (a) for a laminar flow through a circular pipe, is

A. 0.5
B. 1.0
C. l.5
D. 2.0
Answer» E.
75.

A fluid particle may possess the displacement of

A. translation
B. rotation
C. distortion
D. all the above.
Answer» E.
76.

In a centrifugual pump casing, the flow of water leaving the impeller, is

A. rectilinear flow
B. radial flow
C. free vortex motion
D. forced vertex.
Answer» D. forced vertex.
77.

For most economical rectangular section of a channel, the depth is kept

A. one-fourth of the width
B. three times the hydraulic radius
C. half the width
D. hydraulic mean depth
Answer» D. hydraulic mean depth
78.

In two dimensional flow the components of velocity are given by u = ax; v = by. The stream lines will be

A. circular
B. parabolic
C. hyperbolic
D. elliptical.
Answer» D. elliptical.
79.

A non-uniform steady flow is through

A. a long tube at a decreasing rate
B. an expanding tube at constant rate
C. an expanding tube at increasing rate
D. a long pipe at increasing rate.
Answer» C. an expanding tube at increasing rate
80.

Most economical section of a circular channel for maximum discharge

A. depth of water = 0.95 diameter of circular section
B. hydraulic mean depth = 0.286 diameter of circular section
C. wetted perimeter = 2.6 diameter of circular section
D. all the above.
Answer» E.
81.

Bernoulli's equation assumes that

A. fluid is non-viscous
B. fluid is homogeneous
C. flow is steady
D. all the above.
Answer» E.
82.

When a body is totally or partially immersed in a fluid, it is buoyed up by a force equal to

A. weight of the body
B. weight of the fluid displaced by the body
C. weight of the body and fluild displaced by the body
D. difference of weights of the fluid displaced and that of the body
Answer» C. weight of the body and fluild displaced by the body
83.

If the atmospheric pressure on the surface of an oil tank (sp. gr. 0.8) is 0.1 kg/cm², the pressure at a depth of 2.5 m, is

A. 1 metre of water
B. 2 metres of water
C. 3 metres of water
D. 3.5 metres of water
Answer» D. 3.5 metres of water
84.

For a most economical rectangular channel, the hydraulic mean depth, is equal to

A. the depth of flow
B. half the depth of flow
C. one-third depth of flow
D. None of these.
Answer» C. one-third depth of flow
85.

The length of hydraulic jump is roughly

A. 2 to 3 times its height
B. 3 to 5 times its height
C. 5 to 7 times its height
D. None of these.
Answer» D. None of these.
86.

For the flow of liquid from an open ended tube (or nozzle) leading to the formation of spray of liquid drops, the number generally applied, is

A. Froude number
B. Weber number
C. Reynold number
D. Mach number.
Answer» C. Reynold number
87.

The discharg formula Q = Cd √2gH x A is used for rectangular

A. small orifices only
B. large orifices only
C. small and large orifices only
D. for all types of orifices.
Answer» C. small and large orifices only
88.

If the pressure at the inlet of a pipe is 90 kg/cm² and pressure drop over the pipe line is 10 kg/cm², the efficiency of transmission, is

A. 66.6%
B. 77.7%
C. 55.5%
D. 88.8%.
Answer» E.
89.

Non-over flow double curvature concrete arch, is provided in

A. Bhakra dam
B. Hirakund dam
C. Nagarjuna Sagar dam
D. Idukki dam.
Answer» E.
90.

The ratio of the hydraulic radius of a pipe running full to the hydraulic radius of a square section of a channel whose side is equal to the diameter of the pipe, is

A. 1
B. 1/2
C. 1/3
D. 3/4
Answer» E.
91.

The intensity of pressure due to sudden closure of a valve of a pipe in which water flows with velocity v, is directly proportional to :

A. square root of the bulk modulus of elasticity of water
B. bulk modulus of elasticity of water
C. specific weight of water
D. none of these.
Answer» B. bulk modulus of elasticity of water
92.

If the total head of the nozzle of a pipe is 37.5 m and discharge is 1 cumec, the power generated is

A. 400 H.P.
B. 450 H.P.
C. 500 H.P.
D. 550 H.P.
Answer» D. 550 H.P.
93.

An ideal fluid

A. is frictionless and incompressible
B. obeys Newton's law of velocity
C. is similar to gas
D. is very viscous.
Answer» B. obeys Newton's law of velocity
94.

Reynold number is the ratio of initial force and

A. viscosity
B. elasticity
C. gravitational force
D. surface tension.
Answer» B. elasticity
95.

A triangular notch is preferred to a rectangular notch because

A. only one reading is required
B. its formula is simple to remember
C. it gives more accurate results for low discharge
D. all the above.
Answer» E.
96.

On a flow net diagram, the distance between two consecutive steam lines at two successive sections are 1 cm and 0.5 cm respectively. If the velocity at the first section is 1 m/sec, the velocity at the second is

A. 1.0 m/sec
B. 0.5 m/sec
C. 2.0 m/sec
D. 2.5 m/sec
Answer» D. 2.5 m/sec
97.

The detention time of a circular tank of diameter d and water depth H, for receiving the sewage Q per hour, is

A. A
B. B
C. C
D. D
Answer» B. B
98.

In an inclined position, a venturimeter records

A. more reading
B. less reading
C. same reading
D. none of these.
Answer» D. none of these.
99.

With a clinging nappe of a weir, the excess discharge, is

A. 6% to 7%
B. 8% to 10%
C. 18% to 20%
D. 25% to 30%
Answer» E.
100.

Flow in pipes is laminar if Reynold number is

A. less than 2100
B. more than 3000
C. between 2100 and 3000
D. none of these.
Answer» B. more than 3000