IFS Agricultural Engineering 2006
Paper-I

Section A
1. Answer any four sub-parts not exceeding 150 words for each sub-part:
a. What are the different stages in the development of gully? Describe them briefly .
b. Calculate the cross-section of a contour bund used to store 24 h excess rainfall of 10 cm. Annual rainfall is about 120 cm with a high intake rate and there is low coverage of crops over the land. The land slope is 4%. Use Cox's formula for VI of contour bund .
c. Design a 150 m long inward sloping bench terrace for a sandy loam soil with an average slope of 15%. The entire width of the terrace acts as a channel which is provided with a uniform grade of 0.6%. Rainfall intensity for the return period and time of concentration is 20 cm/h. VI 1.06 m. Area of terrace 0.09 ha, runoff coefficient 0.3, riser side slope shoulder bund height 30 cm, bottom width 75 cm, side slope Manning's n 0.04 .
d. Define critical slope length. How is it related to the land slope
e. What is runoff inducement in relation to water harvesting? Discuss briefly five methods of runoff inducements .
2. Answer the following questions
a. Design the dimensions of a weir used to discharge excess runoff through a contour bund for the following conditions Land slope top width of bund 45 cm, height of bund 60 cm, height of crest above GL 30 cm, side slope of bund VI 1 length of bund 400 m. Intensity of rainfall for the return period and time of concentration 12 cm/h. During the peak rainfall, constant infiltration rate 2.5 cm/h. No water is stored behind the bund before the peak rainfall occurs. Determine the volume of water stored behind the bund before it starts flowing
b. Define neutral slope of a pipe outlet mathematically and give the discharge equation of a drop inlet spillway for pipe flow condition. Explain the terms .
3. Answer the following questions
a. Indicate the correct answer by writing the appropriate alphabet:
1) The main effects of the atmosphere on electromagnetic radiation are
i) cloud and rain
ii) reflection and refraction
iii)scattering and absorption
2) The problem generally encountered in aerial photographs is
i) colour and shading
ii) tilt and relief displacement
iii)camera and height
3) Orthophoto can be defined as
i) overlapped maps
ii) corrected photos
iii)overlapped photos
4) Atmospheric window allows light
i) transmission
ii) reflection
iii)scattering
5) Remote sensing sensors are sensitive to
i) reflected and emitted energy
ii) eye and camera
iii)film
b. Define the term ‘image processing’ and list its main steps
c. Briefly explain supervised classification and unsupervised classification
d. Write briefly about Spatial resolution and Temporal resolution of remote sensing satellites. Write the spatial resolution of LISS HI and PAN sensors onboard IRS ID Satellite 1).
e. Discuss the different types of soil movement by wind erosion
f. Give a formula for computing the distance of full protection from a shelterbelt. Explain the terms
4. Answer the following questions
a. A pond dyke rests on a permeable foundation. With the help of an explanatory sketch, give a formula for determination of seepage loss through the dyke .
b. A rectangular pond (50 m × 100 has top dyke width of 3 side slope 1 on both sides and a height of 5 m. The depth of water in the pond is 4.5 m and the depth of impermeable bed below the ground level is 5 m. Coefficient of permeability of dyke material 0.5 mm/mm and that of the foundation 0.1 mm/mm. Determine the seepage loss through the pond dyke in m3 per day
c. Enlist ten points to be considered for selection of a suitable site for farm pond

Section B
5. Answer any four sub-parts not exceeding 150 words for each sub-part:
a. For steady radial flow in unconfined aquifer, derive an expression for discharge .
b. With the help of characteristic curves, explain the method of selection of centrifugal pumps .
c. Potato with 60 cm effective root zone depth is grown in a soil with field capacity and permanent wilting point of 22 and respectively. Irrigation is applied after 40% depletion of the available moisture. Apparent sp. Gr. Of soil 1.60. Calculate the depth of irrigation required if a pump delivers 10 us discharge, how much time it will take for the irrigation of 1.0 ha assuming no loss of water
d. List ten conditions for installation of weirs .
e. Runoff water from a watershed enters into a drainage area for 8 hours at the rate of 3 m3/s.
The total rainfall during 24-hour period is 12 cm and the total infiltration during the period is 4 cm. If the total drainage area is 200 ha and the crop can tolerate a pounding of 10 cm, calculate the drainage coefficient of the land .
6. Answer the following questions
a. Design a most economical trapezoidal channel section to carry a discharge of 15 m3/s in a bed slope of 1 in 3500. The side slope is 1.5: 1 and Manning's n 0.02
b. List five specific advantages of submersible pumps over turbine pumps .
c. Explain manometric head and gross head of centrifugal pump .
7. Answer the following questions
a. A rectangular farm of 10 ha (500 m 200 is to be fenced by barbed wires with concrete poles. Estimate the cost of fencing with six rows of barbed wire. Assume suitable values for spacing of posts and different prices
b. Enlist ten conditions under which a sprinicler irrigation is more suitable than surface method .
c. What are the advantages of using fertilizer with irrigation water in a sprinkler system? With the help of a sketch, explain the method of adding fertilizer through the suction side of a centrifugal pump
8. Answer the following questions
a. Design a drainage channel in sandy loam soil to drain 800 ha of land. Maximum permissible velocity in the sandy loam soil is 0.60 cm/s and the drainage coefficient is 2.0 cm. Side slope of channel 1 Manning's n 0.02. The channel gradient is 1/3500
b. Discuss briefly the following
1) Relief wells
2) Mole drains
3) Vertical drains
4) Buried drains