The most economical section of a rectangular channel is one which has hydraulic mean depth or hydraulic radius equal to (A) Half the depth (B) Half the breadth (C) Twice the depth (D) Twice the breadth

The most economical section of a rectangular channel is one which has hydraulic mean depth or
hydraulic radius equal to
(A) Half the depth
(B) Half the breadth
(C) Twice the depth
(D) Twice the breadth
by

1 Answer

Answer :

Answer: Option A
by

Related questions

The most economical section of a trapezoidal channel is one which has hydraulic mean depth equal to (A) 1/2 × depth (B) 1/2 × breadth (C) 1/2 × sloping side (D) 1/4 × (depth + breadth)

Description : The most economical section of a trapezoidal channel is one which has hydraulic mean depth equal to (A) 1/2 × depth (B) 1/2 × breadth (C) 1/2 × sloping side (D) 1/4 × (depth + breadth)

Last Answer : Answer: Option A

The discharge through a channel of rectangular section will be maximum, if (A) Its depth is twice the breadth (B) Its breadth is twice the depth (C) Its depth is thrice the breadth (D) Its breadth is thrice the depth

Description : The discharge through a channel of rectangular section will be maximum, if (A) Its depth is twice the breadth (B) Its breadth is twice the depth (C) Its depth is thrice the breadth (D) Its breadth is thrice the depth

Last Answer : Answer: Option B

The ratio of the depth of flow to the hydraulic radius for the most economical trapezoidal section, in open channel flow is (A) 0.5 (B) 1 (C) 1.5 (D) 2

Description : The ratio of the depth of flow to the hydraulic radius for the most economical trapezoidal section, in open channel flow is (A) 0.5 (B) 1 (C) 1.5 (D) 2

Last Answer : (D) 2

The discharge through a channel of trapezoidal section is maximum when (A) Width of channel at the top is equal to twice the width at the bottom (B) Depth of channel is equal to the width at the bottom (C) The sloping side is equal to half the width at the top (D) The sloping side is equal to the width at the bottom

Description : The discharge through a channel of trapezoidal section is maximum when (A) Width of channel at the top is equal to twice the width at the bottom (B) Depth of channel is equal to the width at the bottom ... equal to half the width at the top (D) The sloping side is equal to the width at the bottom

Last Answer : Answer: Option C

If 'x' is the depth of flow in an open channel of large width, then the hydraulic radius is equal to (A) x (B) x/2 (C) x/3 (D) 2x/3

Description : If 'x' is the depth of flow in an open channel of large width, then the hydraulic radius is equal to (A) x (B) x/2 (C) x/3 (D) 2x/3

Last Answer : (A) x

What is most economical channel section ? Write conditions for rectangular channel section to be economical .

Description : What is most economical channel section ? Write conditions for rectangular channel section to be economical . 

Last Answer : Most Economical Channel Section: - A channel which gives max. discharge for a given c/s area & bed slope and coefficient of roughness is called as Most Economical Channel Section. OR The most economical channel ... amount of excavation. Condition for rectangular channel: - i) b = 2d ii) R = d/2

In open channel flow in a rectangular channel, the ratio between the critical depth and the initial depth, when a hydraulic jump occurs is (A) 0.5 (B) 0.84 (C) 1.84 (D) 1.25

Description : In open channel flow in a rectangular channel, the ratio between the critical depth and the initial depth, when a hydraulic jump occurs is (A) 0.5 (B) 0.84 (C) 1.84 (D) 1.25

Last Answer : (C) 1.84

In a flow net (A) Flow lines and equipotential lines cross each other at right angles (B) Fields are rectangles whose length is twice the breadth (C) Smaller the dimensions of the field, smaller will be the hydraulic gradient and velocity of flow through it (D) For homogeneous soil, the curves are smooth and circular

Description : In a flow net (A) Flow lines and equipotential lines cross each other at right angles (B) Fields are rectangles whose length is twice the breadth (C) Smaller the dimensions of the field, ... gradient and velocity of flow through it (D) For homogeneous soil, the curves are smooth and circular

Last Answer : Option A

If L, B and D length, breadth and depth of water in a rectangular sedimentation tank of total discharge Q, the settling velocity, is (A) Q/H(B) Q/D(C) Q/(D × B) (D) Q/(L × B)

Description : If L, B and D length, breadth and depth of water in a rectangular sedimentation tank of total  discharge Q, the settling velocity, is  (A) Q/H (B) Q/D (C) Q/(D × B)  (D) Q/(L × B) 

Last Answer : (D) Q/(L × B) 

A simply supported uniform rectangular bar breadth b, depth d and length L carries an isolated load W at its mid-span. The same bar experiences an extension e under same tensile load. The ratio of the maximum deflection to the elongation, is (A) L/d (B) L/2d (C) (L/2d)² (D) (L/3d)²

Description : A simply supported uniform rectangular bar breadth b, depth d and length L carries an isolated  load W at its mid-span. The same bar experiences an extension e under same tensile load. The  ratio of the maximum deflection to the ... (A) L/d (B) L/2d (C) (L/2d)² (D) (L/3d)²

Last Answer : (C) (L/2d)

The breadth of rib in a T-beam should at least be equal to __________the depth of rib (a) One –half (b) One –third (c) One-fourth (d) One –sixth

Description : The breadth of rib in a T-beam should at least be equal to __________the depth of rib (a) One –half (b) One –third (c) One-fourth (d) One –sixth

Last Answer : (b) One –third

Pick up the correct statement from the following: A. The circular section of sewers provides maximum hydraulic mean depth B. The circular sewers are provided for separate sewerage system C. The circular sewers work efficiently if the sections run at least half full D. All the above

Description : Pick up the correct statement from the following: A. The circular section of sewers provides maximum hydraulic mean depth B. The circular sewers are provided for separate sewerage system C. The circular sewers work efficiently if the sections run at least half full D. All the above

Last Answer : ANS: D

According to Chezy's formula, the discharge through an open channel is (where A = Area of flow, C = Chezy's constant, m = Hydraulic mean depth, and i = Uniform slope in bed) (A) A × m × i) (B) C × m × i) (C) AC × m × i) (D) mi × A × C)

Description : According to Chezy's formula, the discharge through an open channel is (where A = Area of flow, C = Chezy's constant, m = Hydraulic mean depth, and i = Uniform slope in bed) (A) A × m × i) (B) C × m × i) (C) AC × m × i) (D) mi × A × C)

Last Answer : Answer: Option C

According to Chezy's formula, the discharge through an open channel is (where A = Area of flow, C = Chezy's constant, m = Hydraulic mean depth, and i = Uniform slope in bed) (A) A × m × i) (B) C × m × i) (C) AC × m × i) (D) mi × A × C)

Description : According to Chezy's formula, the discharge through an open channel is (where A = Area of flow, C = Chezy's constant, m = Hydraulic mean depth, and i = Uniform slope in bed) (A) A × m × i) (B) C × m × i) (C) AC × m × i) (D) mi × A × C)

Last Answer : Answer: Option C

The hydraulic mean depth or the hydraulic radius is the ratio of (A) Area of flow and wetted perimeter (B) Wetted perimeter and diameter of pipe (C) Velocity of flow and area of flow (D) None of these

Description : The hydraulic mean depth or the hydraulic radius is the ratio of (A) Area of flow and wetted perimeter (B) Wetted perimeter and diameter of pipe (C) Velocity of flow and area of flow (D) None of these

Last Answer : Answer: Option A

channel is said to be of most economical cross-section, if (A) It gives maximum discharge for a given cross-sectional area and bed slope (B) It has minimum wetted perimeter (C) It involves lesser excavation for the designed amount of discharge (D) All of the above

Description : channel is said to be of most economical cross-section, if (A) It gives maximum discharge for a given cross-sectional area and bed slope (B) It has minimum wetted perimeter (C) It involves lesser excavation for the designed amount of discharge (D) All of the above

Last Answer : Answer: Option D

Best side slope for most economical trapezoidal section in open channel flow, wherein side slopes are defined by : X horizontal to 1 vertical, is when X equals : (a) 0.404 (b) 0.500 (c) 0.577 (d) 0.673

Description : Best side slope for most economical trapezoidal section in open channel flow, wherein side slopes are defined by : X horizontal to 1 vertical, is when X equals : (a) 0.404 (b) 0.500 (c) 0.577 (d) 0.673

Last Answer : (c) 0.577

The critical depth meter is used to measure (A) Velocity of flow in an open channel (B) Depth of flow in an open channel (C) Hydraulic jump (D) Depth of channel

Description : The critical depth meter is used to measure (A) Velocity of flow in an open channel (B) Depth of flow in an open channel (C) Hydraulic jump (D) Depth of channel

Last Answer : Answer: Option C

A queen closer is a (A) Brick laid with its length parallel to the face or direction of wall (B) Brick laid with its breadth parallel to the face or direction of wall (C) Brick having the same length and depth as the other bricks but half the breadth (D) Brick with half the width at one end and full width at the other

Description : A queen closer is a (A) Brick laid with its length parallel to the face or direction of wall (B) Brick laid with its breadth parallel to the face or direction of wall (C) Brick having the same ... bricks but half the breadth (D) Brick with half the width at one end and full width at the other

Last Answer : Answer: Option C

For hydraulically efficient rectangular channel of bed width 4.0 m, the depth of flow is (a) 4 m (b) 0.5 m (c) 1 m (d) 2 m

Description : For hydraulically efficient rectangular channel of bed width 4.0 m, the depth of flow is (a) 4 m (b) 0.5 m (c) 1 m (d) 2 m

Last Answer : (d) 2 m

The moment of inertia of a rectangular section of width and depth about an axis passing through C.G. and parallel to its width is (A) BD²/6 (B) BD3 /6 (C) BD3 /12 (D) B²D/6

Description : The moment of inertia of a rectangular section of width and depth about an axis passing  through C.G. and parallel to its width is  (A) BD²/6  (B) BD3 /6  (C) BD3 /12  (D) B²D/6 

Last Answer : (C) BD3 /12 

The section modulus of a rectangular section is proportional to (A) Area of the section (B) Square of the area of the section (C) Product of the area and depth (D) Product of the area and width

Description : The section modulus of a rectangular section is proportional to  (A) Area of the section  (B) Square of the area of the section  (C) Product of the area and depth  (D) Product of the area and width

Last Answer : (A) Area of the section

If the permissible stress in steel in tension is 140 N/mm², then the depth of neutral axis for a singly reinforced rectangular balanced section will be (A) 0.35 d (B) 0.40 d (C) 0.45 d (D) Dependent on grade of concrete also

Description : If the permissible stress in steel in tension is 140 N/mm², then the depth of neutral axis for a singly reinforced rectangular balanced section will be (A) 0.35 d (B) 0.40 d (C) 0.45 d (D) Dependent on grade of concrete also

Last Answer : Answer: Option B

The effective depth of a singly reinforced rectangular beam is 300mm. the section is over-reinforced and the neutral axis is 120mm below the top. If the maximum stress attained by concrete is 5N/mn2 and the modular ratio is 18, then the stress developed in the steel will (a) 130N/mm2 (b) 135N/mm2 (c) 160N/mm2 (d) 180N/mm2

Description : The effective depth of a singly reinforced rectangular beam is 300mm. the section is over-reinforced and the neutral axis is 120mm below the top. If the maximum stress attained by concrete is 5N/mn2 and the modular ratio ... in the steel will (a) 130N/mm2 (b) 135N/mm2 (c) 160N/mm2 (d) 180N/mm2

Last Answer : (b) 135N/mm2

The most efficient section of a channel is (A) Triangular (B) Rectangular (C) Square (D) Trapezoidal

Description : The most efficient section of a channel is (A) Triangular (B) Rectangular (C) Square (D) Trapezoidal

Last Answer : Answer: Option D

The highest efficiency is obtained with a channel of __________ section. (A) Circular (B) Square (C) Rectangular (D) Trapezoidal

Description : The highest efficiency is obtained with a channel of __________ section. (A) Circular (B) Square (C) Rectangular (D) Trapezoidal

Last Answer : Answer: Option D

The radius of gyration of a rectangular section is not proportional to (A) Square root of the moment of inertia (B) Square root of the inverse of the area (C) Square root of the moment of inertia divided by area of the section (D) None of these

Description : The radius of gyration of a rectangular section is not proportional to  (A) Square root of the moment of inertia  (B) Square root of the inverse of the area  (C) Square root of the moment of inertia divided by area of the section  (D) None of these 

Last Answer : (D) None of these 

Hydraulic mean depth (Dm) for a circular pipe of diameter 'D' flowing full is 0.25 D. For a circular channel, at Dm = 0.3 D, gives the condition for the maximum (A) Flow rate (B) Mean velocity (C) Both 'a' & 'b' (D) Neither 'a' nor 'b

Description : Hydraulic mean depth (Dm) for a circular pipe of diameter 'D' flowing full is 0.25 D. For a circular channel, at Dm = 0.3 D, gives the condition for the maximum (A) Flow rate (B) Mean velocity (C) Both 'a' & 'b' (D) Neither 'a' nor 'b

Last Answer : (B) Mean velocity

The ratio of the hydraulic radius to the diameter of the channel, for maximum mean velocity of flow in a circular channel, in open channel flow is (A) 0.3 (B) 0.9 (C) 0.03 (D) 0.66

Description : The ratio of the hydraulic radius to the diameter of the channel, for maximum mean velocity of flow in a circular channel, in open channel flow is (A) 0.3 (B) 0.9 (C) 0.03 (D) 0.66

Last Answer : (A) 0.3

In general, the depth of slab should be ---------------- the minimum depth required for balanced section. [ A ] Equal to [ B ] Less than [ C ] Greater than [ D ] Half of

Description : In general, the depth of slab should be ---------------- the minimum depth required for balanced section. [ A ] Equal to [ B ] Less than [ C ] Greater than [ D ] Half of

Last Answer : [ C ] Greater than

The most economical channel section for the fluid flow is the one for which the discharge is maximum for a given cross-sectional area. Vertical velocity distribution in an open channel for laminar flow can be assumed to be (A) Parabolic (B) Hyperbolic (C) Straight line (D) None of these

Description : The most economical channel section for the fluid flow is the one for which the discharge is maximum for a given cross-sectional area. Vertical velocity distribution in an open channel for laminar flow can be assumed to be (A) Parabolic (B) Hyperbolic (C) Straight line (D) None of these

Last Answer : (A) Parabolic

The discharge through a large rectangular orifice is given by (where H1 = Height of the liquid above the top of the orifice, H2 = Height of the liquid above the bottom of the orifice, b = Breadth of the orifice, and Cd = Coefficient of discharge) (A) Q = (2/3) Cd × b × (2g) × (H2 - H1) (B) Q = (2/3) Cd × b × (2g) × (H2 1/2 - H1 1/2) (C) Q = (2/3) Cd × b × (2g) × (H2 3/2 - H1 3/2) (D) Q = (2/3) Cd × b × (2g) × (H2 2 - H1 2 )

Description : The discharge through a large rectangular orifice is given by (where H1 = Height of the liquid above the top of the orifice, H2 = Height of the liquid above the bottom of the orifice, b = Breadth of the orifice, and Cd = Coefficient of ... H1 3/2) (D) Q = (2/3) Cd b (2g) (H2 2 - H1 2 )

Last Answer : Answer: Option C

The length, breadth and height of a rectangular parallelopiped are in the ratios 6 : 3 : 1. If the surface area of a cube is equal -Maths 9th

Description : The length, breadth and height of a rectangular parallelopiped are in the ratios 6 : 3 : 1. If the surface area of a cube is equal -Maths 9th

Last Answer : answer:

The width of a rectangular sewer is twice its depth while discharging 1.5 m/sec. The width of the sewer is A. 0.68 m B. 0.88 m C. 1.36 m D. 1.76 m

Description : The width of a rectangular sewer is twice its depth while discharging 1.5 m/sec. The width of the sewer is A. 0.68 m B. 0.88 m C. 1.36 m D. 1.76 m

Last Answer : ANS: C

The areas of cross-section of a square beam and a circular beam subjected to equal bending moments, are same. (A) Circular beam is more economical (B) Square beam is more economical (C) Both the beams are equally strong (D) Both the beams are equally economical

Description : The areas of cross-section of a square beam and a circular beam subjected to equal bending  moments, are same.  (A) Circular beam is more economical  (B) Square beam is more economical  (C) Both the beams are equally strong  (D) Both the beams are equally economical 

Last Answer : (B) Square beam is more economical 

A circular sewer section is preferred to because A. It is cheaper in construction B. It provides maximum area for a given perimeter C. It provides maximum hydraulic mean depth D. All the above

Description : A circular sewer section is preferred to because A. It is cheaper in construction B. It provides maximum area for a given perimeter C. It provides maximum hydraulic mean depth D. All the above

Last Answer : ANS: D

A hydraulic jump in a control meter will be formed above the control, if its original (A) Depth is more than critical depth (B) Depth is less than the critical depth (C) Depth is equal to critical depth (D) None of these

Description : A hydraulic jump in a control meter will be formed above the control, if its original (A) Depth is more than critical depth (B) Depth is less than the critical depth (C) Depth is equal to critical depth (D) None of these

Last Answer : Answer: Option B

The losses in open channel flow generally vary as the (A) Inverse of the roughness (B) First power of the roughness (C) Square of the velocity (D) Inverse square of hydraulic radius

Description : The losses in open channel flow generally vary as the (A) Inverse of the roughness (B) First power of the roughness (C) Square of the velocity (D) Inverse square of hydraulic radius

Last Answer : (B) First power of the roughness

Define hydraulic radius for trapezoidal channel.

Description : Define hydraulic radius for trapezoidal channel.

Last Answer : Hydraulic Radius: It is the ratio of the wetted area to wetted perimeter. It is also called as Hydraulic mean depth. R= Wetted area / Wetted perimeter = A/P

The discharge through a channel of circular section will be maximum when the depth of water is __________ the diameter of the circular channel. (A) 0.34 times (B) 0.67 times (C) 0.81 times (D) 0.95 times

Description : The discharge through a channel of circular section will be maximum when the depth of water is __________ the diameter of the circular channel. (A) 0.34 times (B) 0.67 times (C) 0.81 times (D) 0.95 times

Last Answer : Answer: Option D

The velocity through a channel of circular section will be maximum when the depth of water is __________ the diameter of the circular channel. (A) 0.34 times (B) 0.67 times (C) 0.81 times (D) 0.95 times

Description : The velocity through a channel of circular section will be maximum when the depth of water is __________ the diameter of the circular channel. (A) 0.34 times (B) 0.67 times (C) 0.81 times (D) 0.95 times

Last Answer : Answer: Option C

If M, I, R, E, F, and Y are the bending moment, moment of inertia, radius of curvature, modulus of elasticity stress and the depth of the neutral axis at section, then (A) M/I = R/E = F/Y (B) I/M = R/E = F/Y (C) M/I = E/R = E/Y (D) M/I = E/R = Y/F

Description : If M, I, R, E, F, and Y are the bending moment, moment of inertia, radius of curvature, modulus of  elasticity stress and the depth of the neutral axis at section, then  (A) M/I = R/E = F/Y (B) I/M = R/E = F/Y (C) M/I = E/R = E/Y (D) M/I = E/R = Y/F

Last Answer : (C) M/I = E/R = E/Y

The ratio of the length and depth of a simply supported rectangular beam which experiences maximum bending stress equal to tensile stress, due to same load at its mid span, is (A) 1/2 (B) 2/3 (C) 1/4 (D) 1/3

Description : The ratio of the length and depth of a simply supported rectangular beam which experiences  maximum bending stress equal to tensile stress, due to same load at its mid span, is  (A) 1/2  (B) 2/3  (C) 1/4  (D) 1/3

Last Answer : (B) 2/3 

The resistance of a strip of copper of rectangular cross-section is 2Ω. A metal of resistivity twice that of ....

Description : The resistance of a strip of copper of rectangular cross-section is 2Ω. A metal of resistivity twice that of copper is coated on its upper surface to a thickness equal to that of copper strip. The resistance of composite strip will be

Last Answer : The resistance of a strip of copper of rectangular cross-section is 2Ω. A metal of resistivity twice that of copper is coated on its upper surface to a thickness equal to that of copper strip. The resistance of composite strip will be 4/3Ω.

How far away from the surface of the Earth does the acceleration due to gravity become ½ of its value at the surface of Earth? It is at a (a) Distance equal to radius (b) Distance equal to half the radius (c) Distance equal to twice the radius (d) Distance equal to 0.414 times the radius

Description : How far away from the surface of the Earth does the acceleration due to gravity become ½ of its value at the surface of Earth? It is at a (a) Distance equal to radius (b) Distance equal to half the radius (c) Distance equal to twice the radius (d) Distance equal to 0.414 times the radius

Last Answer : Ans:(d)

Consider the following statements in respect of critical flow in a wide rectangular channel: 1. The specific energy is minimum for a given discharge. 2. The discharge is maximum for a given specific energy 3. The specific force is minimum for a given discharge. 4. The Froude number is equal to unity. Which of these statements are correct? (a) 1 , 2 & 3 only (b) 1, 2, 3 & 4 (c) 1, 2 & 4 only (d) 2, 3 & 4 only

Description : Consider the following statements in respect of critical flow in a wide rectangular channel: 1. The specific energy is minimum for a given discharge. 2. The discharge is maximum for a given specific energy 3. The specific force is minimum for a ... b) 1, 2, 3 & 4 (c) 1, 2 & 4 only (d) 2, 3 & 4 only

Last Answer : (b) 1, 2, 3 & 4

Hydraulic radius of 6" × 12" cross-section, is __________ inches. (A) 2 (B) 0.5 (C) 1.5 (D) None of these

Description : Hydraulic radius of 6" × 12" cross-section, is __________ inches. (A) 2 (B) 0.5 (C) 1.5 (D) None of these

Last Answer : (A) 2

Auger boring (A) Is the most primitive method for making a hole in the ground (B) Is generally employed in cohesive and other self soils above water table (C) Is most economical upto a depth of 5 metres (D) All the above

Description : Auger boring (A) Is the most primitive method for making a hole in the ground (B) Is generally employed in cohesive and other self soils above water table (C) Is most economical upto a depth of 5 metres (D) All the above

Last Answer : Answer: Option D

Grillage foundation (A) Is used to transfer heavy structural loads from steel columns to a soil having low bearing capacity (B) Is light and economical (C) Does not require deep cutting as the required base area with required pressure intensity is obtained at a shallow depth (D) All the above

Description : Grillage foundation (A) Is used to transfer heavy structural loads from steel columns to a soil having low bearing capacity (B) Is light and economical (C) Does not require deep cutting as the required base area with required pressure intensity is obtained at a shallow depth (D) All the above

Last Answer : Answer: Option D