AGRICULTURAL ENGINEERING PREBOARD EXAM 2014 PREPARED BY: ENGR. ROLAND J. MACANA Flashcards
A refrigeration equipment fabricator sold an ice drop making machine with the condition that in
case the machine will not be able to produce the guaranteed capacity, he will deduct from the
agreed price of the machine the loss of revenue that the buyer will incur during the economic life of
the machine which is set at 5 years., plus 12% cost of money. One month after the machine was
delivered, the buyer complained to the fabricator that he is not getting the guaranteed production.
After series of test, it was determined that the buyer would be losing P4000 worth of unrealized
sales per year. Assuming no increase in operation cost if guaranteed production were attained, how
much must the buyer deduct from the agreed price of the machine?
P14,419.10
It consists of two gangs wherein one gang is located behind the other at an angle and the harrow
is operated in an offset position in relation to the tractor centerline
Offset Disc Harrow
In Agricultural Machinery Method of Sampling, certain color is used for specific function such as
hazard warning display
Red
In Agricultural Machinery Method of Sampling, certain color is used for specific function such as
failure or serious malfunction; requires immediate attention
Red
It is a system in which tillage of the total soil surface is performed in such a way that plant residue
is specifically left on or near the soil surface
Mulch Tillage
The peak transmission efficiency of the tractor shall be at least___
85%
The noise emitted by the tractor measured 50 mm away from the operator’s ear level shall not be
more than ___db (A).
92
The peak transmission efficiency of the axle-driven rotary tiller shall be at least ____.
80%
It is part of the plow which lifts, inverts and throws the furrow slice to one side
Moldboard
It is part of the plow which lifts, inverts and throws the furrow slice to one side
Moldboard
Determine the time in hours to plow a 3-ha field using a 15-cm animal-drawn plow at a speed of
4 kph and efficiency of 75%
2.75 Days
In an ideal Otto engine, the combustion of fuel occurs at
constant volume
The ideal air-fuel ratio for using kerosene as an engine fuel is
15:1
Sprayers are used primarily for the application of
pesticides
Which of the following does not belong to the group of positive displacement pumps?
propeller pump
It helps keep engine running, by its inertia, during idle strokes (intake, compression, exhaust)
Flywheel
Receives power generated in the cylinder.
Piston
Engine size. This is given by the bore and stroke of the engine. For instance, a 100 mm X 124 mm.
Given the above engine size, compute the piston displacement. Compute the total cylinder volume in the problem above. Compute the Compression ratio in problem above (given that CV= PD/6)
piston displacement 973, 400 cubic mm
cylinder volume 1, 135, 633.30 cubic mm
Compression ratio 7
The piston moves from TDC to BDC. The inlet valve is opened to allow the fuel mixture to enter
and fill the partial vacuum created by the movement of the piston
Intake Stroke
The piston returns from BDC to TDC, sweeping out burnt fuel through the exhaust valve which
has been opened.
Exhaust Stroke
The intake valve is closed, the exhaust valve remains closed and the piston moves from BDC to
TDC compressing the fuel mixture into the clearance volume, thereby raising its temperature.
Compression Stroke
When the piston approaches TDC during the compression stoke, a spark ignites the fuel mixture
and the expanding gases drive the piston from TDC to BDC
Power Stroke
It is a device used to connect or disconnect the source of power to the rest of the transmission
system
clutch
Suppose a plough 150 mm wide is furrowing 60 mm deep in a particular soil that offers a
resistance of 2 N per square centimeter of cross section. Calculate the total draft of the plough.
180 N
Assuming that the plough has a cutting width of 150 mm as in the problem above, and is pulled a
distance of 3.6 km in one hour
. 0.24 Hp
Recommended plant spacing for corn: between rows and between plants (in cm).
90 & 60
Suppose a 5X150 mm seed drill is to plant 80 kg of wheat seed per hectaare. If the diameter of
its drive wheel is 1000 mm, calculate the width of the seed drill. From the problem above, calculate the length of travel necessary for the drill to cover o.1 Ha. From the problem above, calculate the number of wheel revolutions to travel 0.1 Ha. From the problem above, compute the amount of seed that should be delivered from each tube
to plant 0.1 Ha
width of the seed drill 0.75 m
length of travel 1333.3 m
wheel revolutions 425
amount of seed 1.6 kg
Mixture of Chemicals in which the chemical (in powder form) remains floating in water and
needs constant agitation to prevent it settling out.
suspension
Fixed Costs are the following except one:
maintenance
Variable costs are the following except one:
labor costs
Supposing the cost of the tractor operated seed drill is to be calculated from the following data:
Tractor used: 40 Kw (maximum PTO)
Tractor Cost 9000 dollar
Life of the Tractor 5 years
Salvage Value 10 percent
Compute the (a.) depreciation cost of the tractor (b.) find the interest on capital at 6 percent (c.) cost of the housing and insurance (d.) total fixed Cost of the tractor (e.) lubrication cost from the problem above assuming fuel cost of 1.78 Dollar (f.) cost of repair and maintenance
a. . 1620 Dollar
b. 297 Dollar
c. 180 Dollar
d. 2097 Dollar
e. 0.27 Dollar
f. 4500 Dollar
It is a mixture of several metals
alloy
If hardened steel is heated to red heat and cooled slowly it becomes softened. It is easier to drill
a machine steel that has been treated in this way.
Annealing
A man borrowed P 2, 000 from a bank and promise to pay the amount for one year. He recceive
only the amount of P 1, 920 after the bank collected an advance interest of P 80.00. What was the
rate of discount and the rate of interest that the bank collected in advance?
4%;
4.17%
If you borrowed money from your friend with simple interest of 12 %, find the present worth of
P 50, 000. 00; which due at the end of 7 months
P 46, 200.00
A price tag of P 1200.00 is payable in 60 days but if paid with in 30 Days it will have a 3% discount.
Find the rate of interest
A bank charges 12% simple interest on a P 300.00 loan. How much will be paid back if the load is
paid back in one lump sum after three years.
John borrowed P50,000.00 from the bank at 25% compounded semi-annually. What is the
the equivalent effective rate of interest?
25.56 %
The amount of P50,000.00 was deposited in the bank earning an interest of 7.5% per annum.
Determine the total amount at the end of 5 years, if the principal and interest were not withdrawn
during the period
P71,781.47
Determine the biogas consumption per day of a household using a 4-inch gas burner at 4 hours
duration per day. The gas consumption of the burner is constant at 0.283 m3/hour
. 1.13 cubic meter
Determine the biogas production per day of an animal farm having 10,000 heads of porkers of
mixed ages. Use a retention period of 35 days. The mean daily manure production of porkers is 2.2
kg/head while the specific gas production for 35-day hydraulic retention time in the digester is
0.065 m3/kg.
. 1430 cubic meter
How many heads of breeding buffalo are needed as source of manure to generate 1,000 m3 of
biogas a day if the retention period is 25 days. The mean daily manure production of breeding
buffalo is 13.5 kg/head while its specific gas production for 25-day manure retention period is half of
that of chicken dung.
405
Determine the required digester volume of a biogas plant that will accommodate manure from a
broiler farm having a capacity of 20,000 heads of mixed ages. Use 30-day retention period and 1:1
manure-water ratio. The mean daily manure production of broiler is 0.025 kg/head while its specific
gas production for 30-day manure retention period is 0.062 m3/kg. Chicken dung density is
950 kg/m3.
25.2 cubic meter
Founder of Agricultural Engineering
. Dr. Felix D. Maramba
It is known as “Agricultural and Fisheries Mechanization Law”
RA 10601
Resolution that requires the indication of the registration, license number and expiry by a
Professional Agricultural Engineer
Resolution no. 270, series of 1993
When was RA 8559 approved?
February 26, 1998
Threshing Efficiency of the Mechanical Grain Thresher
99.8 %
Hulling Efficiency of the Rice Mill
80 %
ACME Engine is a brand of Engine coming from
Italy
What is the allowable noise level of hammer mill (dB)?
96
What is the Heating Value of Coconut Shell?
9965 BTU/lb
What is the field efficiency of the Rice Reaper?
. 65 %
Ecological Solid Waste Management of 2000
RA 9003
A machine has an initial cost of P50,000 and a salvage value of P10,000 after five years.
Determine the depreciation after three years using straight line depreciation
An asset is purchased for P120,000.00. Its estimated life is 10 years, after which it will be sold for
P12,000.00. Find the depreciation for the second year using the sum-of-the-years-digit method
In the environment, by how many times is methane destructive than carbon dioxide?
The toxic gaseous by-product of geothermal power plants that is trace in biogas.
a. Hydrogen Sulfide
Rice grain from which the hull, the germ, the outer bran layers and the greater part of the inner
bran layers have been removed but part of the lengthwise streaks of the bran layers may still be
present on 15 % to 40% of the sample grains
.It is a radial distance between the addendum circle and the pitch circle
addendum
This fan causes the air/gas to enter from the side fan wheel, deflected 90 degrees and
accelerates due to centrifugal force as it flows over the fan blades and exits the fan housing
Centrifugal
Engr. Macana borrows P 100,000.00 at 10% effective annual interest. He must pay back the loan
over 30 years with uniform monthly payments due on the first day of each month. What does Engr.
Macana pay each month?
P879.00
A new boiler was installed by a textile plant at a total cost of P300,000.00 and projected to have
a useful life of 15 years. At the end of its useful life, it is estimated to have a salvage value of
P30,000.00. Determine its capitalized cost if interest is 18% compounded annually
P 324, 604.17
The fertility of a field is such that maximum corn yields are obtained with a population of 54,000
plants per hectare. The rows are 0.75 m apart and an average emergence of 80% is expected. How
seeds per hill should be planted if the hills are 0.5 m apart.
2-3 seeds per hill
A 5-m self-propelled combine makes an average stop of 4 minutes everytime its 2-ton grain
tank is to be unloaded. The yield of the 20-ha field is 40 tons. The operating speed is 4.8 kph. The
time for turning on the headland at the ends of the 500-m field is 15 seconds. Compute the
(a.) theoretical field capacity (b) actual field capacity (c) field efficiency
a. 2.4 Ha/hr
b. 2 Ha/hr
c. 83.33%
Which of the following does not belong to the group of positive displacement pumps?
a. propeller pump b. force pump c. lift pump d. rotary pump
a. propeller pump
According to the National Irrigation Administration (NIA) water requirement for the
rice production is:
10 mm/day
A field measuring 45mX90 m is to be preepared using a 1-m upland power tiller at a speed of
3kph. Assume a 10% overlap between passings and 9 seconds turn around time at the end of each
pass. Determine the field efficiency in going the shorter field direction:
a. 77%
The three-phase electric motor is characterized as:
low first cost- high operating cost
The three-phase electric motor is characterized as:
low first cost- high operating cost
Benefit-Cost Ratio is the ratio of the present worth of the benefit stream over the present worth
of cost stream extending over a period of time usually the life of the machine. Decision rule is to
accept projects with:
. BCR≥1
Which is true of the following?
a. Internal Rate of Return is the maximum interest rate the project can pay for the
use of money if the project is to breakeven. At this point, the Net Present Value=0
and BCR = 1
b. The decision rule is that the IRR of the project should be higher than the prevailing
interest rate of the bank.
c. none of the choices
d. both a and b
d. both a and b
Level of operation where the investment neither produces a profit nor incurs a loss
Break-even point
Assuming, you have signed an engineering plan of FMR of a certain LGU despite having an
expired license, how much would be the highest possible amount of fine that you must pay upon
conviction? Assuming that the court decision also includes imprisonment, how long you will be staying
in prison?
0.2 Million
36 months
It is any material added to the tractor for the purpose of enhancing traction or stability.
. Ballast
Cost that do not involve cash payments, but rather represent the recovery of past expenditures
over a fixed period of time
Credit
Which of the following has the highest soil draft?
a. clay loam b. sandy clay c. silty clay d. heavy clay
d. heavy clay
A soil pulverizer with pulley diameter of 4 inches runs at a shaft speed of 3,000 rpm. The 10 hp
diesel engine will be used to operate at a speed of 1740 rpm. What will be the size of the pulley for
the engine?
7 in
Protective device designed and fitted to prevent dangerous parts being reached from all sides
casing
What is the force required to pull a single moldboard plow on a clay loam soil having a width and
depth of cut of 30 cm and 15 cm, respectively. Soil draft is 8 psi.
a. 253 kg
Agricultural Engineering Road Map Goals (2013-2020), how many Agricultural Engineers will be
needed?
10000
A grove that is placed on a shaft to prevent pulley from slippage.A grove that is placed on a shaft
to prevent pulley from slippage
keyway
A rice thresher is to be driven by 10-hp gasoline engine using a V-belt drive. The engine is 1800
rpm while the thresher cylinder speed is 650 rpm. The diameter of the engine pulley is 4 inches.
What will be the recommended diameter of the thresher’s pulley?
10 in
Firing order for 8 cylinder V piston
1-8-7-3-6-5-4-2
Conversion of solid fuel into combustible carbon monoxide through thermochemical reaction.
Gasification
.Instrument measuring engine speed
. tachometer
The heat energy content of coconut shell charcoal is 14223 BTU/lb. How many kilo calories are
there in 10 kilos of coconut shell charcoal.
d.78, 852.3 Kcal
The heat energy content of coconut shell charcoal is 14223 BTU/lb. How many kilo calories are
there in 10 kilos of coconut shell charcoal.
d.78, 852.3 Kcal
. If the center distances of the three pulleys above are: 24 in., 36 in., and 42 in. for pulley 4 to 6, 6
to 8, and 8 to 4 pulley diameters, respectively, what is the recommended length of the belt needed
above? Assume an angle of arc of 135° for pulley 6 and 8, while 90° for pulley 4 inch diameter.
. 101.56 in
A power tiller was tested on a 10 m wide plot. During the test, the machine made 22 rounds to
complete the plowing operation using two-0.3 m diameter disk plow. What is the average swath of
the power tiller?
. 0.23 m
