Font size
WorksheetsDAY 42 WORKSHEET LSGD (IRRIGATION)
Total questions: 15
Worksheet time: 12mins
In a zoned earth dam, if the central core becomes cracked due to differential settlement, the most immediate danger is —
Overtopping of dam
Excess uplift at the heel
Seepage through cracks causing piping failure
Loss of phreatic control
In a hydro-electric project, the difference between gross head and net head mainly represents —
Head losses due to friction & turbulence in conveyance system
Energy used for priming the turbine
Velocity head at penstock exit
Storage head losses during drawdown
For the same discharge, a syphon aqueduct is costlier than an aqueduct because —
It requires RCC barrels under pressure
It is longer in length
It carries flow in open channel
It needs no energy dissipation arrangement
A detention reservoir differs from a retarding reservoir primarily by —
Providing gated control on its outlets
Being located on smaller tributaries
Not submerging agricultural land
Storing only surcharge water
Which of the following ensures stability of an arch dam when strong abutments are available but foundation is weak?
Buttress effect
Arch action transferring load to abutments
Trapezoidal base widening
Weight of dam alone
TRUE/FALSE
In a gravity dam, uplift pressure always acts vertically upward and is uniform throughout the base.
(a)
TRUE/FALSE
In a lined canal, higher flow velocity than an unlined one is permissible because lining reduces friction and seepage.
(a)
Assertion (A): A surge tank minimizes the water-hammer effect in long penstocks. Reason (R): It absorbs sudden rise of pressure by storing water when load decreases and releases it when load increases.
Both A and R true, R explains A
Both A and R true but R not explanation
A true, R false
A false, R true
The junction of the upstream face of a gravity dam with its foundation is called the (a) .
The head of water available at the turbine inlet after deducting losses in penstock is known as (a) .
When a canal passes through hard rocky strata, the preferred type of canal is __________ canal.
The storage between Minimum Pool Level (MPL) and Full Reservoir Level (FRL) represents (a) storage.
In a hydroelectric scheme, the overall efficiency = __________ × __________ × __________.
(a)
Match the Following
A. Aqueduct - 1. Canal below drainage (pipe flow in canal)
B. Super passage - 2. Canal and drain at same level
C. Level crossing - 3. Canal over drainage (open flow)
D. Syphon aqueduct - 4. Canal below drainage (open flow)
A–1, B–4, C–2, D–3
A–4, B–1, C–2, D–3
A–4, B–1, C–3, D–2
A–4, B–2, C–1, D–3
MATCH THE FOLLOWING
A. Forebay - 1. Reduces water-hammer pressure
B. Surge tank - 2. Receives water directly from penstock
C. Turbine - 3. Acts as intermediate storage before penstock
D. Draft tube - 4. Carries water from forebay to power house
A–1, B–3, C–4, D–2
A–3, B–1, C–4, D–2
A–3, B–4, C–1, D–2
A–3, B–1, C–2, D–4
