Water Management MCQs with Answers | Agriculture – Page 3

Question 41 Water Management

When the sloping face of a river bank is protected by stone pitching against scour, what is the pitching extended beyond the toe towards the river called?

Correct answer C. Launching apron

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Question 42 Water Management

What is a groyne that points upstream, against the direction of flow, called?

Correct answer B. Repelling

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Question 43 Water Management

If a weir floor is built as a continuous reinforced structure with the divide piers, so that their weight keeps it safe against uplift, what is it called?

Correct answer B. Non-gravity weir

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Question 44 Water Management

What is the rise in river water level upstream caused by building a weir called?

Correct answer B. Afflux

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Question 45 Water Management

Through which structures should silt-free water be supplied to canals?

Correct answer D. Head sluices

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Question 46 Water Management

What is the masonry or concrete wall built at 90° to the weir axis to separate the main weir from the under-sluices called?

Correct answer C. Divide wall

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Question 47 Water Management

A fish ladder dissipates flow energy so that fish downstream can move upstream easily. Within what range does the flow velocity in it lie?

Correct answer B. 3.0 – 3.5 m/sec

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Question 48 Water Management

To stop floodwater spilling over the gates, a wall resting on piers is built from pond level to high flood level along the regulator and resists water pressure by its weight. What is it called?

Correct answer D. Breast wall

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Question 49 Water Management

What are structures built on the river bed just upstream of a canal head regulator, so that only clearer water enters the canal, called?

Correct answer B. Silt excluders

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Question 50 Water Management

In a hydraulic jump, the depth before the jump is called the initial depth. What is the depth after the jump called?

Correct answer D. Sequent depth

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Question 51 Water Management

Hydraulic structures built on which soils most often fail because of undermining and uplift pressure?

Correct answer B. Permeable

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Question 52 Water Management

At the end of a hydraulic structure, when the upward force of subsoil water just equals the submerged weight of the soil grains, what is the exit gradient called?

Correct answer B. Critical exit gradient

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Question 53 Water Management

Hydraulic structures today are designed using flow net theory. Who gave this theory?

Correct answer C. Khosla

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Question 54 Water Management

To prevent scouring at the end of a hydraulic structure, what must be provided at the exit point?

Correct answer D. Vertical cutoff

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Question 55 Water Management

For a strong hydraulic jump that dissipates maximum energy, at what slope should the downstream glacis be built?

Correct answer A. 3:1 to 5:1

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Question 56 Water Management

After a weir is built, the downstream river bed keeps eroding and gradually lowers. What is this process called?

Correct answer C. Retrogression

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Question 57 Water Management

In Lacey’s wetted perimeter formula used for a weir waterway, P = ____ (Q)1/2. What is the constant?

Correct answer A. 4.75

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Question 58 Water Management

What is the pool built downstream of a hydraulic structure to dissipate the energy of falling water by providing a water cushion called?

Correct answer A. Cistern

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Question 59 Water Management

What is a module or outlet called whose discharge depends on the difference in head between the distributary and the watercourse?

Correct answer A. Non-modular

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Question 60 Water Management

What is an outlet whose discharge depends on the water level in the distributary called?

Correct answer B. Flexible module

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