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Indian Forest Services (Main)
Examination-2025
DJSM-B-AGRE
AGRICULTURAL ENGINEERING
Time Allowed : Three Hours
Paper - II
Maximum Marks : 200
Question Paper Specific Instructions
Please read each of the following instructions carefully before attempting
questions:
There are EIGHT questions in all, out of which FIVE are to be attempted.
Questions no. 1 and 5 are compulsory. Out of the remaining SIX questions, THREE are
to be attempted selecting at least ONE question from each of the two Sections A and B.
Attempts of questions shall be counted in sequential order. Unless struck off, attempt of a
question shall be counted even if attempted partly. Any page or portion of the page left
blank in the Question-cum-Answer Booklet must be clearly struck off.
All questions carry equal marks. The number of marks carried by a question/part is
indicated against it.
Answers must be written in ENGLISH only.
Unless otherwise mentioned, symbols and notations have their usual standard meanings.
Assume suitable data, if necessary and indicate the same clearly.
Neat sketches may be drawn, wherever required.
DJSM-B-AGRE
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SECTION A 3
Ql. (a) Define indicated thermal efficiency and relative efficiency of an
IC engine. Why is relative efficiency preferred as a measure of engine
performance ? 8
(b) @ Define depreciation and list the different methods employed in
calculating depreciation. Also, indicate which method is common
for farm machines. 4
Gi) A disk harrow with a draft of 18 N is required to be pulled at a
speed of 4 km/h in a firm untilled field by a tractor having
maximum PTO power rating of 40 kW.
Calculate the actual PTO power needed to pull the harrow, if the
tractive and transmission coefficient for a 2-wheel drive tractor
for the untilled firm soil is 0-75. 4
(c) Enlist the reasons for lubricating the different moving parts of
IC engine. Also, state what you understand by ‘Multigrade’
lubricating oil. 8
(d) What is Solar Constant ? Write about the instruments that are used to
measure solar energy. 8
(e) Define the following : 8
(i) Cetane number
(ii) Volumetric efficiency of IC engine
(iii) Firing order in multicylinder engine
(iv) Compression ratio
Q2. (a) Write short notes on the following : 5x3=15
(63) Pressurised radiator cap
Gi) Nozzles of agricultural sprayers
(iii) | Accessories of tractor drawn mouldboard plough
(iv) Gasification of biomass
(v) Valve timing diagram of a 4-stroke cycle IC engine
(b) | Write down the functions of a Carburettor. Explain with the help of a
sketch the principle and working of a simple Float-type Carburettor. 15
(ce) Discuss the different types of solar energy collectors and their
applications. 10
DJSM-B-AGRE 2
Q3. (a) What type of governor is generally used in tractors manufactured in
India ? Explain its working principle and operation with the help of a
suitable diagram.
<b); —.@)
(ii)
What types of disc harrow fall under the category of
Double Action’ disc harrow ? Explain their working with a line
sketch.
A tractor weighing 28-5 kN with a front wheel reaction of 9:0 kN,
is in static position on a horizontal surface. The wheelbase is
2-08 m. Calculate the horizontal distance from the rear axle
centreline to the centre of gravity. Also, calculate the rear wheel
reaction and explain with reason if it is a 2-wheel drive or a
4-wheel drive tractor.
(c) | Write down the classification of Induction Motors. List the factors that
should be considered for selecting the right type of motor.
Q4. (a) Classify the digester of a biogas plant on the basis of construction
as well as on the basis of gas storage. Also, discuss the utilization of
biogas for different applications.
<b); =U)
(ii)
Write down the functions of Fuel Injection Pump of a tractor
engine. Discuss the importance of fuel viscosity in fuel injection
system.
What is Atomization ? Discuss the main fluid properties that
affect droplet size in agricultural spraying.
(c) Classify implements on the basis of how they are attached to a
wheel-type Agricultural Tractor and discuss each.
DJSM-B-AGRE
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Q5. (a)
(b)
(c)
(d)
(e)
Q6. (a)
(b)
(c)
(d)
SECTION B
Write short notes on the following :
@ Specific Humidity
Gi) Dew Point (DP) Temperature
(iii) Wet Bulb (WB) Temperature
(iv) Decortication of Oilseeds
Explain different types of food packaging materials with their
characteristics.
Define Fineness Modulus.
Using fineness modulus, determine the average particle size with the
following data :
IS Sieve Size 100 | 70 | 50} 40 | 20 | 15 | PAN
Percentage (%) of particles
retained on each sieve wd nto, Lincs ites Maashads Nala We
Define electrical amplifying elements and discuss their voltage
amplification, current amplification and gain.
Explain in ascending order the data storage hierarchy in a computer.
With the help of a line diagram, discuss Vertical Cone Rice Whitener.
Also, discuss its advantages and disadvantages.
5000 kg of apples are to be cooled from 25°C to 10°C in 24 hours. Specific
heat of apple is 3-25 kJ/kg°C. The heat of respiration in 24 hours is
3400 kJ per tonne of apples. Due to different sources, the infiltration of
heat is 4100 kJ per tonne of apples during 24 hours. The lighting load is
150 W. Calculate the refrigeration capacity [tonne of refrigeration (TR)]
of machine required.
Note : 1 TR = 3:5 kW = 210 kJ/min.
Write the principle of operation of the following transducer elements and
mention their input and output variables :
G) Bourdon gauge
Gi) Venturimeter/Orifice meter
(iii) Piezo-electric device
Gv) Solar cell
Write the algorithm and flowchart to find the sum of two numbers.
DJSM-B-AGRE : 4
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Q8.
(a)
(b)
(c)
(d)
(a)
(b)
(c)
Discuss various advantages and limitations of ice cream ingredients
such as milk fat, milk-solids-not-fat, sugar, stabilizer, emulsifier, total
solids, flavour and colour.
A bucket elevator is installed to be used up to a height of 25 m for
vertically lifting foodgrains (750 kg/m®). Each bucket has a volume of
3500 cc and spaced 40 cm apart on a belt. The centre-to-centre distance
between head and foot wheel is 25-30 metres. The head pulley is 30 cm
in diameter and rotates on a shaft of 5 cm diameter. The belt and the
empty buckets weigh on an average 5 kg per metre length. Assume
degree of lifting as 80% and coefficient of friction as 0-4 at the axle of the
pulley.
Find the speed and power required to lift 4 tonnes of foodgrains
(750 kg/m®) per hour.
What is Data ? Describe the procedure of data processing to obtain
information for decision-making.
With a neat sketch, explain the cistern-type manometer used for
measuring static pressure.
What are the objectives of the Tempering-Degerming (TD) method in
corn dry milling ? Describe the basic operations involved in the TD
method.
Describe the various steps in modern wheat flour milling.
Define Shrikhand. Discuss the standardised method of preparation of
Shrikhand.
DJSM-B-AGRE 5
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