Deck 11: Canals and Irrigation

Question 1

The bed of a canal is lowered in case of

A)syphon aqueduct
B)canal syphon
C)level crossing
D)all of these

Answer 1

canal syphon

Question 2

Inglis formula is used for estimating flood discharge for

A)the catchments of former Bombay Presidency
B)the catchments of oil Hyderabad State
C)the Madras catchments
D)none of the above

Answer 2

the catchments of former Bombay Presidency

Question 3

Lining of a canal

A)assures economical water distribution
B)reduces possibility of breaching
C)increases available head for power generation
D)all of the above

Answer 3

all of the above

Question 4

Which of the following statements is wrong?

A)The top of dowel is kept above the free supply level by a margin of free board.
B)The dowels are provided as a measure of safety for automobiles driven on the service roads
C)The dowels act as curbs on the side of roadway towards the canal
D)none of the above

Question 5

The flooding is also termed as wild flooding.

Question 6

The tortuosity of a meandering river is always

A)equal to
B)less than
C)greater than

Question 7

According to Khosla's theory, the undermining of the floor starts from the

A)starting end
B)tail end
C)intermediate point
D)foundation bed

Question 8

The irrigation water is said to be unsatisfactory, if it contains

A)chemicals toxic to plants or to persons using plants as food
B)chemicals which react with the soil to produce unsatisfactory moisture characteristics
C)bacteria injurious to persons or animals eating plants irrigated with water
D)all of the above

Question 9

Which of the salt present in water is harmful for cultivation purposes?

A)Sodium carbonate
B)Potassium sulphate
C)Calcium sulphate
D)none of these

Question 10

The width of dowel is, usually, kept from

A)0.1 m to 0.3 m
B)0.3 m to 0.6 m
C)0.6 m to 0.9 m
D)0.9 m to 1.2 m

Question 11

A device which ensures a constant discharge of water passing from one channel to another irrespective of water level in each within certain specified limits, is called

A)flume
B)module
C)meter
D)none of these

Question 12

The sodium carbonate lining consists of at lest

A)6% sodium carbonate and 10% clay
B)10% sodium carbonate and 6% clay
C)1% sodium carbonate and 6% clay
D)1% clay and 6% sodium carbonate

Question 13

The degree of sinuosity is the ratio between the

A)meander length and width of meander
B)meander length and the width of river
C)curved length and the straight air distance
D)none of these

Question 14

The excapes must lead the surplus water to natural drainage.

Question 15

The kor depth for rice is 19 cm and kor period is 14 days. The outlet factor for the crop in hectares per cumec will be

A)437
B)637
C)837
D)1037

Question 16

The repelling groyne is constructed in such a way that it is pointing towards

A)upstream
B)downstream

Question 17

The estimation of flood can be made

A)by physical indication of past floods
B)by flood discharge formulae
C)by unit hydrograph
D)all of these

Question 18

The amount of water required to fill up the pore spaces in soil particles by replacing all air held in pore spaces, is known as

A)field capacity
B)saturation capacity
C)available moisture
D)all of these

Question 19

The crops require maximum water during

A)first watering before sowing the crops
B)last watering before harvesting
C)first watering when the crop has grown a fwd centimetres
D)all of the above

Question 20

The efficiency is a measure of conservation of head by an outlet.

Question 21

The incoherent alluvium is a soil composed of loose granular graded material which can be scoured with the same ease with which it is deposited.

Question 22

When the difference in weir crest and downstream river bed is limited into 3 metres, the weir, generally used is

A)vertical drop weir
B)drystone slope weir
C)concrete slope weir
D)parabolic weir

Question 23

A structure constructed in an irrigation canal for the purpose of wasting some of its water, is known as a

A)fall
B)escape
C)regulator
D)none of these

Question 24

The Inglis type fall makes use of

A)straight
B)horizontl
C)vertical

Question 25

A groyne is a structure constructed transverse to the river flow and extend from the bank into the river upto a certain limit.