WorksheetsPIPE ELEMENTS 1
Total questions: 138
Worksheet time: 1hrs 9mins
Name
Class
Date
1.
Find the work posses for a helium gas at 20C.
a)
A. 609 KJ/kg
b)
B. 168 KJ/kg
c)
C. 229 KJ/kg
d)
D. 339 KJ/kg
2.
Two kilogram of gas is confined in a 1m^3 tank 200kpa and 88degC. What type of gas is in the tank?
a)
A. Helium
b)
B. Ethane
c)
C. Methane
d)
D. Ethane
3.
Find the enthalpy of the helium if its internal energy is 200KJ/Kg.
a)
A. 144 kj/kg
b)
B. 223.42 KJ/kg
c)
C. 333.42 KJ/kg
d)
D. 168 KJ/kg
4.
Compute the mass of a 2m^3 propane at 280 kpa and 40degC
a)
A. 6.47
b)
B. 5.1
c)
C. 10.20
d)
D. 9.47
5.
Compute the air flow in ft^3/min of mechanical ventilation required to exhaust an accumulation of refrigerant due to leaks of the system capable of revolving air from the machinery room for a mass of 4lbs refrigerant.
a)
A. 200
b)
B. 210
c)
C. 220
d)
D. 230
6.
Compute the free aperture cross section in m^2 for the ventilation of a machinery room in the mass of refrigerant is 9kg.
a)
A. 0.314
b)
B. 0.414
c)
C. 0.514
d)
D. 0.614
7.
A 29.53” X 39.37” pressure vessel contains ammonia with f=0.041. compute the minimum required discharge capacity of relief device in kg/hr.
a)
A. 106.71 kg/hr
b)
B. 108.7 kg/hr
c)
C. 110.71 kg/hr
d)
D. 112.71 kg/hr
8.
Compute the maximum length of discharge puipe installed on the outlet of a pressure- relief device in feet for the internal pipe diameter of 0.5 inch and rated discharge capacity is 8lb/min of air. The rated pressure of relief valve is 16psig.
a)
A. 0.286ft.
b)
B. 0.386 ft.
c)
C. 0.386 ft.
d)
D. 0.586 ft
9.
A thermal power plant has a heat rate of 11,363 Btu/kw-hr. find the thermal efficiency of the plant.
a)
A. 28%
b)
B. 30%
c)
C. 34%
d)
D. 40%
10.
What is the hydraulic gradient of a 1 mile, 17 inches inside diameter pipe when 3300 gal/ml of water flow with f= .03?
a)
A. 0.00714
b)
B. 0.00614
c)
C. 0.00234
d)
D. 0.00187
11.
Find the loss of head in the pipe entrance if speed of flow is 10 m/s.
a)
A. 5.10m
b)
B. 10.2m
c)
C. 17.4m
d)
D. 2.55m
12.
Wet material containing 220% moisture (dry basis) is to be dried at the rate of 1.5 kg/s in a continuous dryer to give a product containing 10% (dry basis). Find the moisture removed, kg/hr.
a)
A. 3543.75 kg/hr
b)
B. 3513.75 kg/hr
c)
C. 3563.75 kg/hr
d)
D. 3593.75 kg/hr
13.
Copra enters a dryer containing 70% moisture and leaves at 7% moisture. Find the moisture removed on each pound of solid in final product.
a)
A. 6.528lb
b)
B. 1.258lb
c)
C. 4.258lb
d)
D. 2.258 lb
14.
A 1m x 1.5m cylindrical tank is full of oil with sg=0.92. find the force acting at the bottom of the tank in dynes
a)
A. 106.33 x 10^3
b)
B. 106.33 x 10^4
c)
C. 106.33 x 10^5
d)
D. 106.33 x 10^6
15.
Air at 10 deg. C and 80 Kpa enters a diffuser of a jet engine steadily with a velocity of 200 m/s. The inlet area of diffuser is 0.40 m^2. Determine the mass flow rate of air.
a)
A. 72.79 kg/s
b)
B. 74.79 kg/s
c)
C. 76.79 kg/s
d)
D. 78.79 kg/s
16.
Consider a refrigeration whose 40 watts light bulb remains on continuously as a result of malfunction of the switch. If the refrigerator has a COP of 1.3 and the cost of electricity is 8 cents per kw-hr, determine the increase in the energy consumption of the refrigerator and its cost per year if the switch is not fixed.
a)
A. P49.59
b)
B. P47.59
c)
C. P 45.59
d)
D. P43.59
17.
A 75hp motor that has an efficiency of 91% is worn out and is replaced by high-efficiency motor that has an efficiency of 95.4%. Determine the reduction in heat gain in room due to higher efficiency under full load conditions.
a)
A. 2.24 KW
b)
B. 2.44 KW
c)
C. 2.64 KW
d)
D. 2.84 KW
18.
A household refrigerator that has a power input of 450 watts and COP of 2.5 is to cool five large watermelons, 10 kg each, if the watermelons are initially at 20 deg. C, determine how long will take for the refrigerator to cool them. the watermelons can be treated as water whose specific heat is 4.2 KJ/kg- K.
a)
A. 2220 seconds
b)
B. 2230 seconds
c)
C. 2240 seconds
d)
D. 2250 seconds
19.
When a maN returns to his wall-sealed house on a summer day, he finds that the house is at 32 deg. C. he turned on the air conditioner which cools the entire house to 20 deg. C in 15 minutes. If COP is 2.5, determine the power drawn by the air-conditioner. Assume the entire mass within the house is 800 kg of air for which Cv = 0.72 KJ/kg-K, Cp = 1.0 KJ/kg-K.
a)
A. 1.072 KW
b)
B. 2.072 KW
c)
C. 3.072 KW
d)
D. 4.702 KW
20.
A heat source at 800 K losses 2000 KJ of heat to a sink at 500 K. Determine the entropy generated during this process.
a)
A. 1.5 KJ./kg
b)
B. 2.5 KJ/kg
c)
C. -2.5 KJ/kg
d)
D. 4 KJ/kg
21.
A helium gas is compressed on in an adiabatic compressor from an initial state of 14 psia and 50 deg. F to a final temperature of 320 deg F in a reversible manner. Determine the exit pressure of helium.
a)
A. 38.5 psia
b)
B. 40.5 psia
c)
C. 42.5 psia
d)
D. 44.5 psia
22.
Air pass thru a nozzle with efficiency of 90%. The velocity of air at the exit is 600 m/s. find the actual velocity at the exit.
a)
A. 382 m/s
b)
B. 540 m/s
c)
C. 458 m/s
d)
D. 568 m/s
23.
A 50 kg of iron casting at 500 K is thrown into a large lake that is at temperature of 285 K. the iron block eventually reaches thermal equilibrium with the lake water. Assuming average specific heat of 0.45 KJ/kg-K for the iron, determine the entropy generated during this process.
a)
A. -12.65 KJ/K
b)
B. 16.97 KJ/K
c)
C. 4.32 KJ/K
d)
D. 6.32 KJ/K
24.
A windmill with a 12 m diameter rotor is to be installed at location where the wind is blowing at an average velocity of 10 m/s. Using standard condition of air (1 atm, 25 deg. C), determine the maximum power that can be generated by the windmill.
a)
A. 68 KW
b)
B. 70 KW
c)
C. 72 KW
d)
D. 74 KW
25.
Consider a large furnace that can supply heat at temperature of 2000 deg. R at a steady rate of 3000 Btu/s. Determine the exergy of this energy. Assume an environment temperature of 77 deg. F.
a)
A. 205.19 KW
b)
B. 2315.19 KW
c)
C. 2325.19 KW
d)
D. 2335.19 KW
26.
A heat engine receives heat from a source at 1200 deg. K at rate of 500 KJ/s and rejects the waste heat to a medium at 300 deg. K. the power output of the heat engine is 180 KW. Determine the irreversibility rate for this process.
a)
A. 190 KW
b)
B. 195 KW
c)
C. 200 KW
d)
D. 205 KW
27.
A dealer advertise that he has just received a shipment of electric resistance heaters for residential buildings that have an efficiency of 100 percent. Assuming an indoor temperature of 21 deg. C and outdoor temperature of 10 deg. C, Determine the second law efficiency of these heaters.
a)
A. 8.74 %
b)
B. 6.75 %
c)
C. 3.74 %
d)
D. 4.74 %
28.
A thermal power plant has a heat rate of 11,363 Btu/hr. find the thermal efficiency of the plant.
a)
A. 34 %
b)
B. 24 %
c)
C. 26 %
d)
D. 30 %
29.
A rigid tank contains 2 kmol of N2 and 6 kmol of CO2 gases at 300 deg. K and 115 Mpa. Find the tank volume using ideal gas equation.
a)
A. 7.33 m^3
b)
B. 5.33 m^3
c)
C. 3.33 m^3
d)
D. 1.33 m^3
30.
A spherical balloon with a diameter of 6 m is filled with helium at 20 deg. C and 200 Kpa. Determine the mole number.
a)
A. 9.28 Kmol
b)
B. 10.28 Kmol
c)
C. 11.28 Kmol
d)
D. 13.28 Kmol
31.
The air in an automobile tire with a volume of 0.53 ft^3 is at 90 deg. F and 20 psig. Determine the amount of air that must be added to raise the pressure to the recommended value of 30 psig. Assume the atmospheric pressure to be 14.6 psia and the temperature and the volume to remain constant.
a)
A. 0.026 lb
b)
B. 0.046 lb
c)
C. 0.066 lb
d)
D. 0.086 lb
32.
A rigid tank contains 20 lbm of air at 20 psia and 70 deg. F. more air is adde to the tank until the pressure and temperature rise to 35 psia and 90 deg. F, respectively. Determine the amount of air added to the tank.
a)
A. 11.73 lb
b)
B. 13.73 lb
c)
C. 15.73 lb
d)
D. 17.73 lb
33.
A rigid tank contains 5 kg of an ideal gas at 4 atm and 40 deg. C. Now a valve is opened, and half of mass of the gas is allowed to escape. If the final pressure in the tank is 1.5 atm. The final temperature in the tanks is:
a)
A. -39 deg. C
b)
B. -30 deg. C
c)
C. 40 deg. C
d)
D. 53 deg. C
34.
The pressure of an automobile tire is measured to be 200 Kpa (gage) before the trip and 220 kpa (gage) after the trip at a location where the atmospheric pressure is 90 kpa. If the temperature of the air in the tire before the trip is 25 deg. C, the air temperature after the trip is:
a)
A. 45.6 deg. C
b)
B. 54.8 deg C.
c)
C. 27.5 deg. C
d)
D. 26.7 deg. C
35.
Water boils at 1 atm pressure in a stainless steel pan on an electric range. It is observed that 2 kg of liquid water evaporates in 30 min. the rate of heat transfer to the water is>
a)
A. 2.97 KW
b)
B. 0.47 KW
c)
C. 2.51 KW
d)
D. 3.12 KW
36.
Consider a person standing on a breezy room at 20 deg. C. Determine the total rate of heat transfer from this person if the exposed surface area and the average outer surface temperature of the person are 1.6 m^2 and 29 deg. C respectively, and the convection heat transfer coefficient is 6 W/m^2 with the emissivity factor of 0.95.
a)
A. 86.40 watts
b)
B. 81.70 watts
c)
C. 198.1 watts
d)
D. 168.1 watts
37.
Water is boiling in a pan on a stove at sea level. During 10 minutes of boiling, it is observed that 200 grams of water has evaporated. Then the rate of heat transfer to the water is
a)
A. 0.84 KJ/min
b)
B. 45.1 KJ/min
c)
C. 41.8 KJ/min
d)
D. 53.5 KJ/min
38.
In a brayton cycles that operates between temperature limits of 300K and 1773K with K=1.4, determine the temperature at the end of the compression (isentropic) for maximum work of the cycle.
a)
A. 700K
b)
B. 690.5K
c)
C. 730K
d)
D. 350K
39.
At 35% solution leaves the absorber and 30% solution enters the absorber. The heat removed from the absorber by cooling water is 547.6 Btu and ammonia is superheated by 10deg. Find the pound per pound of ammonia gas from the evaporating coils.
a)
A. 11
b)
B. 12
c)
C. 13
d)
D. 14
40.
A carnot refrigeration system operates at Tmax./Tmin.=1.5, Find the KW per to of refrigeration.
a)
A. 1.91
b)
B. 2.15
c)
C. 1.76
d)
D. 1.55
41.
Assume 8ft^3 of air at 100psi, 100degF are compressed isothermally to a volume of 2ft^3. For each of end state the process, find the bulk modulus.
a)
A. 400 and 100 psi
b)
B. 400 and 110 psi
c)
C. 400 and 120 psi
d)
D. 400 and 130 psi
42.
Predict the pressure of nitrogen gas at T=200K and v=0.00385 m^3/kg and b=0.00141 m^3/kg; a=0.178 m^2 kpa/kg^2. Use van der waals equation,
a)
A. 15,331 kpa
b)
B. 14,331 kpa
c)
C. 13,331 kpa
d)
D. 12,331 kpa
43.
Francis turbine is to be operated at a speed of 600rpm and with discharge of 4m^3/s. if r1=0.6m, beta1=110deg, and the blade height B is 10cm, what should be the guide angle a1 for non separating flow condition at the runner entrance ?
a)
A. 14.4 deg
b)
B. 15.4 deg
c)
C. 16.4 deg
d)
D. 17.4 deg
44.
The total head of fan is 187m and has a static pressure of 210mm of water gage, what is the velocity of air flowing if density of air is 1.15 kg/m^3 ?
a)
A. 6.85 m/sec
b)
B. 3.45 m/sec
c)
C. 4.39 m/sec
d)
D. 9.28 m/sec
45.
A fan delivers 5.7 m^3/sec. at a static pressure of 5.08 cm of water when operating at a speed of 400rpm. The power input required is 2.963 KW. If 7.05 m^3/sec. are desired in the same fan and installation, find the pressure in cm of water.
a)
A. 7.77
b)
B. 17.14
c)
C. 11.43
d)
D. 5.08
46.
A rigid container is closed at one end and measures 8 in diameter by 12 in long. The container is held vertices and slowly moved downward until the pressure in the container is 17psia. What will be the depth of the top of the container from the free water surface?
a)
A. 42.36in
b)
B. 59.29in
c)
C. 63.69in
d)
D. 69.82in
47.
A turbo-charged, 16 cylinder, Vee-type diesel engine has an air consumption of 3,000 kg/hr per cylinder at rated load and speed, this air is drawn in through a filter by a centrifugal compressor directly connected to the exhaust gas turbine. The temperature of the air from the compressor is 135 DegC and a counter flow air cooler reduces the air temperature to 45 degC before it goes to the engine suction header. Cooling water enters air cooler 30 degC and leaves at 40 degC. Calculate the log mean temperature difference.
a)
A. 47.23 DegC
b)
B. 87.82 degC
c)
C. 43.34 degC
d)
D. 65.42 degC
48.
Water is flowing in a pipe with radius of 30 cm at a velocity of 5 m/sec at the temperature in the pipe. The density and viscosity of the water are as follows density = 997.9 kg/sec viscosity = 1.131 Pa. what is the Reynolds number of this situation?
a)
A. 2847
b)
B. 96.2
c)
C. 3100
d)
D. 140
49.
Compute the amount of condensate form during 10 minutes warm-up of 180 meter pipe conveyors the saturated steam with enthalpy vaporization hfg = 1,947.6 kj/kg. the minimum external temperature of pipe is 2 DegC. The final temperature of pipe is 195 degC. The specific heat of pipe material is 0.6 kj/kg-C. the specific weight if 28 g/m.
a)
A. 249.69 kg
b)
B. 982.45 kg
c)
C. 299.64 kg
d)
D. 423.45 kg
50.
The discharge pressure of an air compressor is 5 times the suction pressure. If volume flow at suction is 0.1 m^3/sec. what is the suction pressure if compressor work is 19.57 kw? (use n = 1.35)
a)
A. 97 Kpa
b)
B. 98 Kpa
c)
C. 99 Kpa
d)
D. 100 Kpa
51.
The initial condition of air in an air
compressor is 93 Kpa and 27 deg. C
and discharges air at 450 Kpa. The bore
and stroke are 355 mm and 381 mm,
respectively with percent clearance of
8% running at 300 rpm. Find he
volume of air at suction.
a)
A. 541.62 m^3/hr
b)
B. 551.62 m^3/hr
c)
C. 561.62 m^3/hr
d)
D. 571.62m^3/hr
52.
An air compressor has a suction
volume of 0.35 m^3/sec at 97 Kpa and
discharges to 650 Kpa. How much
power is saved by the compressor if
there are two stages?
a)
A. 27 KW
b)
B. 16.54 KW
c)
C. 13.86 KW
d)
D. 11.58 KW
53.
A two stage air compressor has an
intercooler pressure of 4 kg/cm^2.
What is the discharge pressure if
suction pressure is 1 kg/cm^2?
a)
A. 3 kg/cm^2
b)
B. 9 kg/cm^2
c)
C. 12 kg/cm^2
d)
D. 16 kg/cm^2
54.
A two-stage air compressor air at 100
Kpa and 22 deg. C discharges to 750
Kpa. If the intercooler intake is 105 deg.
C, Determine the value of n.
a)
A. 1.400
b)
B. 1.326
c)
C. 1.345
d)
D. 1.288
55.
A single acting air compressor has a
volumetric efficiency of 89%, operates
at 500 rpm. It takes in air at 100 Kpa
and 30 deg. C and discharges it at 600
Kpa. The air handled is 8 m^3/min
measured at discharge condition. If
compression is isentropic, find mean
effective pressure in Kpa.
a)
A. 233.34
b)
B. 973.17
c)
C. 198.34
d)
D. 204.82
56.
Water-jacketed air compressor handles
.0343 m^3/s of air entering at 96.5Kpa
and 21 deg. C and leaving at 480 Kpa
and 132 deg. C; 10.9 kg/h of cooling
water enters the jacket at 15 deg. C and
leaves at 21 deg. C, Determine the
compressor brake power?
a)
A. 26.163 kw
b)
B. 62.650 kw
c)
C. 84.44 kw
d)
D. 19.33 kw
57.
A double suction centrifugal pumps
delivers 20 ft^3/sec of water at head of
12 m and running at 650 rpm. What is
the specific speed of the pump?
a)
A. 5014.12 rpm
b)
B. 6453.12 rpm
c)
C. 2770.73 rpm
d)
D. 9968.73 rpm
58.
Determine the number of stages
needed for a centrifugal pump if it
used to deliver 400 gal/min of water
and pump power of 15 Hp. Each
impeller develops a head of 30 ft.
a)
A. 8
b)
B. 4
c)
C. 5
d)
D. 7
59.
The suction pressure of a pump reads 3
in. of mercury vacuum and discharge
pressure reads 140 psi is use to deliver
120 gpm of water with specific volume
of 0.0163 ft^3/lb. Determine the pump
work.
a)
A. 4.6 KW
b)
B. 5.7 KW
c)
C. 7.4 KW
d)
D. 8.4 KW
60.
A submersible pump delivers 350 gpm
of water to a height of 5 ft from the
ground. The pump were installed 150
m below the ground level and a
drawdown of 8 ft during the operation,
if the water level is 25 ft above the
pump, determine the pump power.
a)
A. 7.13 KW
b)
B. 4.86 KW
c)
C. 7.24 KW
d)
D. 9.27 KW
61.
A vacuum pump is used to drain a
flooded mine shaft of 20 deg. C waer.
The pump pressure of water at this
temperature is 2.34 Kpa. The pump is
incapable of lifting the water higher
than 16 m. what is the atmospheric
pressure.
a)
A. 159.30
b)
B. 132.33
c)
C. 198.22
d)
D. 171.9
62.
A submersible, multi-stage, centrifugal
deep well pump 260 gpm capacity is
installed in a well 27 feet below the
static water level and running at 3000
rpm. Drawdown when pumping at
rated capacity is 10 feet. The pump
delivers the water into a 25,000 gallons
capacity overhead storage tank. Total
discharge head developed by pump,
including friction in piping is 243 feet.
Calculate the diameter of the impeller
of this pump in inches if each impeller
diameter developed a head of 38 ft.
a)
A. 3.28
b)
B. 5.33
c)
C. 3.71
d)
D. 6.34
63.
A fan draws 1.42 m^3 per second of air
at a static pressure of 2.54 cm of water
through a duct 300 mm diameter and
discharges it through a duct of 275 mm
diameter. Determine the static fan
efficiency if total fan mechanical is 75%
and air is measured at 25 deg. C and
760 mm Hg.
a)
A. 50.11%
b)
B. 53.69%
c)
C. 65.67%
d)
D. 45.34%
64.
A water coolers uses 50lb/hr of melting
ice to cool running water from 80deg F
to 42deg F. based on the inside coil area
U=110 btu/hr-ft^2-F. Find the gpm of
water cooled.
a)
A. 0.10 GPM
b)
B. 0.21 GPM
c)
C. 0.38 GPM
d)
D. 0.45 GPM
65.
The charge in a diesel engine consist of
18.34 grams of fuel, with lower heating
value of 42,571 KJ/KG, and 409 grams
of fuel and products of combustion. At
the beginning of compression, t1-
60degC, let Rk=14. For constant
Cp=1.11 KJ/KG-C, what should be the
cut-off ratio in the corresponding ideal
cycle ?
a)
A. 2.05
b)
B. 2.34
c)
C. 5.34
d)
D. 2.79
66.
The gain of entropy during nonflow
process of 5lb of air at 60degF is 0.162
Btu/R. find the V1/V2
a)
A. 3.35
b)
B. 0.259
c)
C. 1.0
d)
D. 0.296
67.
An auditorium seating 1500 people is
to be maintained at 80degF dry bulb
and 65degF wet bulb temp. when
outdoor air is at 91degfF dry bulb and
75degF wet bulb. Solar heat loads is
110,000 btu/hr and supply air is at
60degF, determine the amount of air
supply.
a)
A. 93,299.17 lb/hr
b)
B. 83,299.17 lb/hr
c)
C. 73,299.17 lb/hr
d)
D. 63,299.17 lb/hr
68.
An engine-generated rated 9000 KVA at
80% power factor, 3 phase, 4160 V has an
efficiency of 90%. If overall plant efficiency
is 28%, what is the heat generated by the
fuel?
a)
A. 18,800 KW
b)
B. 28,800 KW
c)
C. 7,500 KW
d)
D. 25,714 KW
69.
The indicated thermal efficiency of a
two stroke diesel engine is 60%. If the
friction power is 15% of the heat
generated, determine the brake thermal
efficiency of the engine.
a)
A. 43%
b)
B. 45%
c)
C. 38%
d)
D. 37%
70.
A 305 mm x 457 mm four stroke single acting diesel engine is rated at 150 KW at 260 rpm. Fuel consumption at rated load is 0.56 Kg/Kw-hr with a heating value of 43,912 kj/kg. Calculate brake thermal efficiency.
a)
A. 10.53%
b)
B. 27.45%
c)
C. 14.64%
d)
D. 18.23%
71.
A waste heat recovery boiler produces 4.8 Mpa (dry Saturated) steam from 104 deg C feed water. The boiler receives energy from 7 kg/sec of 954 deg C dry air. After passing through the waste heat boiler, the temperature of the air has been reduced to 343 degC. How much steam in kg is produced per second? Note at 4.60 Mpa dry 10 saturated, h = 2796.
a)
A. 1.30
b)
B. 0.92
c)
C. 1.81
d)
D. 3.43
72.
Diesel electric plant supplies energy for
meralco, during a 24-hour period, the
plant consumed 240 gallons of fuel at
28 degC and produced 3930 KW-hr.
industrial fuel used is 28 deg API and
was purchased at P30 per liter at 15,6
degC. What is the cost of fuel be to
produced one KW-hr?
a)
A. 6.87
b)
B. 1.10
c)
C. 41.07
d)
D. 5.00
73.
In a gas turbine unit, air enters the
combustion chamber at 550 Kpa, 227
degC and 43 m/s. the products of
combustion leave the combustor at 511
Kpa, 1004 degC and 180 m/s. liquid
fuel enters with a heating value of
43,000 kj/kg. for Fuel-air ratio of
0.0029. what is the combustor efficiency
of the unit in percent?
a)
A. 70.38%
b)
B. 79.30%
c)
C. 75.38%
d)
D. 82.38%
74.
The specific speed of turbine is 85 rpm
and running at 450 rpm. If the head is
20 m and generator efficiency is 90%.
What is the maximum power delivered
by the generator?
a)
A. 450.51 KW
b)
B. 354.52 KW
c)
C. 650.53 KW
d)
D. 835.57 KW
75.
A perfect gas has a value of R= 58.8 ft-lb/lb-
R and K= 1.26. if 20 Btu are added to 10 lbs
of his gas at constant volume when initial
temperature is 90 degF find the final
temperature.
a)
A. 97 degF
b)
B. 104 degF
c)
C. 154 degF
d)
D. 185degF
76.
Ammonia weighing 22 kgs is confirmed
inside a cylinder equipped with a piston has
an initial pressure of 413 Kpa at 35 degC if
3200 KJ of heat is added to the ammonia
until its final pressure and temperature are
413 Kpa and 100 DegC respectively, what is
the amount of work done by the fluid in KJ?
a)
A. 667
b)
B. 304
c)
C. 420
d)
D. 502
77.
A tank contains 90 ft^3 of air at a pressure
of 350 Psig; of the air is cooled until its
pressure and temperature decreases to 200
Psig and 70 DegF respectively, what is the
decrease in internal energy?
a)
A. 6232.09 Btu
b)
B. -5552 Btu
c)
C. 5552 Btu
d)
D. -6232.09 Btu
78.
A large mining company was provided
with a 3 m^3 of compressed air tank. Air
pressure in the tank drops from 700 kpa to
160 kpa while the temperature remains
constants at 28 degC, what percentage has
the mass of air in the tank been reduced?
a)
A. 74.00
b)
B. 72.45
c)
C. 76.56
d)
D. 78.57
79.
A 4 m^3/hr pump delivers water to a pressure tank. At the start, the gage reads 138 Kpa until reads 276 KPa and then pump was shut off, The volume of the tank is 100 liters. At 276 Kpa the water occupied 2/3 of the tank volume. Determine the volume of water that can be taken out until the gage reads 138 Kpa.
a)
A. 31.20 liters
b)
B. 34.59 liters
c)
C. 16.67 liters
d)
D. 29.50 liters
80.
A refrigeration plant is rated at 15 tons capacity. How many pounds of air per hour will it cool from 70 to 90 DegF at constant pressure.
a)
A. 50,000 lb/hr
b)
B. 37,500 lb/hr
c)
C. 52,000 lb/hr
d)
D. 45,000 lb/hr
81.
an air standard engine has a compression ratio 18 and a cut-off ratio 4. If the intrake air pressure and temperature are 100 kpa and 27deg C, find the work in KJ per kg.
a)
A. 2976
b)
B. 2166
c)
C. 1582
d)
D. 2751
82.
determine the air standard efficiency of an operating on the diesel cycle with clearance of 6%, when the suction pressure is 99.97 kpa and the fuel is injected for 7% of the stroke. Assume k=1.4.
a)
A. 62.11%
b)
B. 51.20%
c)
C. 73.58%
d)
D. 60.02%
83.
steam at 2Mpa and 250deg C in a rigid cylinder is cooled until the quality is 30%, Find the heat rejected from the cylinder.
a)
A. -432.23
b)
B. -926.26
c)
C. -1265.02
d)
D. 1082.34
84.
The following coal has the following ultimate analysis by weight:
C-70.5%
H2-4.5%
O2 = 6.0%
N2 = 1.0%
S= 3.0%
ASH=11%
Moisture=4%
A stocker fired boiler of 195,00 kg/hr steaming capacity used this coal as fuel. Calculate the volume of air in m^3/hr with air at 60 deg. F and 14.7 psia pressure if boiler efficiency is 70% and FE-1.10
a)
A. 234,019 m^3/hr
b)
B. 215,830 m^3/hr
c)
C. 213,830 m^3/hr
d)
D. 264,830 m^3/hr
85.
23.5 kg of steam per second at 5 Mpa and 400 deg. C is produced by a steam generator. The fedwater enters the economizer at 145 deg. C and leaves at 205 deg. C. the steam leaves the boiler drum with a quality of 98%. The unit consumes 3 kg of coal per second as received having a heating value of 25,102 KJ/kg. What would be the overall efficiency of the unit in percent?
Steam properties: At 5 Mpa and 400 deg.
C: h3195.7 KJ/kg at 5 Mpa; hf1154.23, hfg=1640.1
At 205 deg C: hf875.04 at 145 deg.
C: hf-1640.1
a)
A. 65.72
b)
B. 80.67
c)
C. 88.28
d)
D. 78.82
86.
In an rankine cycle steam enters the turbine 12
the turbine at 2.5 Mpa (enthalpies and
entropies given) and condenser of 50 kPa
(properties are given) what is the thermal
efficiency of the cycle?.
a)
A. 25.55%
b)
B. 45.23%
c)
C. 34.23%
d)
D. 12.34%
87.
A thermal power plant generates 5 MW and
the heat generated by the fuel is 13,000
Kj/sec. if the thermal efficiency is 6.15% ,
find the power needed for the auxiliaries.
a)
A. 310 Kw
b)
B. 300 Kw
c)
C. 400 Kw
d)
D. 350 Kw
88.
Francis Turbine, the Pressure gage
leading to the turbine casing reads 380
Kpa. The velocity of water entering a
turbine is 0 m/sec, if not hoad of the
turbine is 45m. find the distance from
center of spiral casing to the ….
a)
A. 3.0 m
b)
B. 3.5 m
c)
C. 4.0 m
d)
D. 4.5 m
89.
A turbine has a mechanical efficiency
of 93% volumetric efficiency of 95%
and total efficiency of 82%. If the
effective head is 40m, find the total
head.
a)
A. 48.72 m
b)
B. 40.72 m
c)
C. 36.22 m
d)
D. 34.72 m
90.
Pelton Type turbine has 25 m head
friction loss of 4.5 m. the total
coefficient of friction head loss (from
morse) is 0.00093 and penstock length
of 80 m, what is the penstock diameter?
a)
A. 1,355.73 mm
b)
B. 3,476.12 mm
c)
C. 6,771.23 mm
d)
D. 1686.73 mm
91.
In an 9,000 KW hydro electric power
plant the over-all efficiency is 88% and
the actual power received by the
customer is 110,000 Kw-hrs for that
day. What is the secondary power
could this plant deliver during the
entire day?
a)
A. 58,960 KW
b)
B. 80,080 KW
c)
C. 65,960 KW
d)
D. 70,960 KW
92.
Pelton type turbine was installed 30 m
below the head gate of the penstock.
The head loss due to friction is 12% of
the given elevation. The length of
penstock is 100 m and coefficient of
friction is 0.00093 determine the power
output in KW (use morse equation)
a)
A. 22,273
b)
B. 23,234
c)
C. 32,345
d)
D. 34,452
93.
Water flows steadily with a velocity of
3.05 m/s in a horizontal pipe having a
diameter of 25.24 cm. at one action of
the pipe the temperature and pressure
of the water are 21 degC and 689.3 Kpa,
respectively. At a distance of 304.8 m
downstream, the pressure is 516.9 Kpa.
What is the friction factor?
a)
A. 0.135
b)
B. 0.0050
c)
C. 0.0307
d)
D. 0.641
94.
A hydro electric plant having a 30 sq.
km reservoir area and 100 m head is
used to generate power. The energy
utilized by the consumers whose load
is connected to the power plant during
a five-hour period is 13.5 x 10^6 Kwh.
The overall generation efficiency is
75%. Find the fall in height of water in
the reservoir after the 5-hour period.
a)
A. 5.13 m
b)
B. 1.32 m
c)
C. 3.21 m
d)
D. 2.20 m
95.
The gas density of chimney is 0.75
kg/m^3 and air density of 1.15
kg/m^3. Find the driving pressure if
the height of chimney is 63.71 m
a)
A. 0.15 KPa
b)
B. 0.25 Kpa
c)
C. 0.35 Kpa
d)
D. 0.45 Kpa
96.
The actual velocity of gas entering in a
chimney is 8 m/sec. the gas
temperature is 25 degC with a gas
constant of 0.267 kj/kg-K. determine
the gas pressure for a mass of gas is
50,00 kg/hr and chimney diameter of
1.39 m
a)
A. 95 Kpa
b)
B. 98 Kpa
c)
C. 101 kpa
d)
D. 92 Kpa
97.
A steam generator with economizer
and air heater has an overall draft loss
of 25.78 cm of water. If the stack gases
are at 177 DegC and if the atmosphere
is at 101.3 Kpa and 28 DegC. What
theoretical height of stack in meters is needed when no draft fan are used?
Assume that the gas constant for the
flue gasses is the same as that for air.
a)
A. 811.10
b)
B. 631.10
c)
C. 651.10
d)
D. 671.10
98.
A foundation measures 12 ft x 14 ft x 15
ft. find the number of sacks of cement
needed for 1:2:4 mixture
a)
A. 302
b)
B. 404
c)
C. 356
d)
D. 598
99.
A rectangular foundation cross-section
has a bed plate dimension of 8 ft x 10 ft.
the uniform clearance on each side is 1
ft. the height of foundation is 4.5 ft. if
the weight of the steel bar
reinforcements needed is ½% of weight
of foundation, find the weight of steel
bars, use concrete density of 2400 Kg/m^3.
a)
A. 173.47
b)
B. 183.47
c)
C. 163.47
d)
D. 153.47
100.
A steam pipe having a surface
temperature of 250 degC passes
through a room where the temperature
is 27 DegC the outside diameter of pipe
is 100 mm and emissivity factor is 0.8
calculate the radiated headloss for 3m
be length.
a)
A. 1,434.47 W
b)
B. 3,746.35 W
c)
C. 2,851 W
d)
D. 3,546.45 W
101.
Brine enters a circulating brine cooler 14
at the rate of 80 m%3/hr at -8 degC,
specific heat of brine is 1.072 kj/kg-K
and specific gravity of 1.12. determine
the tons of refrigeration.
a)
A. 53.5 TR
b)
B. 65.3 TR
c)
C. 33.5 TR
d)
D. 56.9 TR
102.
At 1.8 Mpa, mixture steam and water has an entropy of 3 KJ/kg Deg K. find the enthalphy of the mixture.
a)
A. 1,627.11KJ/kg
b)
B. 1,533.33 KJ/kg
c)
C. 1,234.45 KJ/kg
d)
D. 1,162.40 KJ/kg
103.
Mixture with 70% quality at 500kpa is heated isothermally until its pressure is 300kpa. Find the heat added during the process.
a)
A. 745.92KJ/kg
b)
B. 535.16 KJ/kg
c)
C. 983.44 KJ/kg
d)
D. 765.34 KJ/kg
104.
A tank contains exactly one kilogram of
water consisting of liquid and vapor in
equilibrium at Mpa. If the liquid contains
one-third and the remaining is vapor of the
volume of the tank, what is the enthalpy of
the contents of the tank?
a)
A. 644.40 KJ/kg
b)
B. 774.40 KJ/kg
c)
C. 785.92 KJ/kg
d)
D. 435.29 KJ/kg
105.
Water substance at 70 bar and 65 degC
enters a boiler tube of constant inside diameter of 25mm. the water leaves the
boiler tube at 50 bar and 700degK at
velocity of 150m/s/ calculate the inlet velocity(m/sec)
a)
A. 1.56
b)
B. 2.51
c)
C. 1.672
d)
D. 3.23
106.
Water substance at 70 bar and 65 degC
enters a boiler tube of constant inside
diameter of 35mm. the water leaves the
boiler tube at 50 bar and 700degK at
velocity of 100m/s/ calculate the inlet
volume flow (li/sec)
a)
A. 0.821
b)
B. 1.261
c)
C. 0.344
d)
D. 1.609
107.
Steam leaves an industrial boiler at 827.4
Kpa and 171.6 deg. C. A portion of the
steam is passed through a throttling
calorimeter and is exhausted to the
atmosphere when the calorimeter pressure
is 101.4 Kpa. How much moisture does the
steam leaving the boiler contain if the
temperature of the steam at the calorimeter
is 115.6 Deg. C.
a)
A. 3.78%
b)
B. 3.08%
c)
C. 4.56%
d)
D. 2.34%
108.
A throttling is connected to the
desuperheated steam line supplying steam
to the auxiliary feed pump on a ship. The
line pressure measrues 2.5 Mpa. The
calorimeter pressure is 110 Kpa and 150
deg. C. determine the entropy of the steam
line.
a)
A. 6.8 KJ/Kg-K
b)
B. 6.2 KJ/Kg-k
c)
C. 6.6 KJ/Kg-k
d)
15
e)
D. 7.5 KJ/Kg-k
109.
Atmospheric pressure at boils 212 deg. F. At
the vacuum pressure at 24 in. Hg, the
temperature is 142 deg F. Find the boiling
temperature when the pressure is increased
by 40 psia from atmospheric.
a)
A. 449.42 F
b)
B. 526.34 F
c)
C. 479.13 F
d)
D. 263.45 F
110.
A certain coal has the following ultimate
analysis:
C = 69% N2 = 5%
H2 = 2.5% S = 7%
Determine the amount of oxygen if the
heating value of fuel is 26,961.45 KJ/Kg.
a)
A. 1.5%
b)
B. 2.5%
c)
C. 3.5%
d)
D. 4.5%
111.
A diesel engine consumed 946 liters of fuel
per day at 35 deg. C. if the fuel was
purchased at 15.6 deg. C and 30 deg. API at
P29.00/li, determine the cost of fuel to
operate the engine per day.
a)
A. P5677.50
b)
B. P4677.50
c)
C. P48,088.90
d)
D. P27,127.76
112.
A cylindrical tank 4m long and 3m diameter
is used for oil storage. How many days can
the tank supply the engine having 27 deg.
API with fuel consumption of 60 kg/hr?
a)
A. 17.53
b)
B. 5.84
c)
C. 12.84
d)
D. 19.84
113.
A logging firm in Isabella operates a Diesel
Electric Plant to supply it’s electric energy
requirements. During a 24 hour period, the
plant consumed 250 gallons of fuel at 80
deg. F and produced 2900 KW-hrs.
Industrial fuel used is 30 deg. API and was
purchased at P30.00/li at 60 deg. F.
Determine the overall thermal efficiency of
the plant.
a)
A. 26.08%
b)
B. 34.23%
c)
C. 28.00%
d)
D. 18.46%
114.
The dry exhaust gas from oil engine has the
following gravimetric analysis :
CO2 = 21.6% O2 = 4.2%
N2 = 74.2%
Specific heats at constant pressure for each
component of the exhaust gas in Kcal/kg-C
are:
CO2 = 0.203 O2 = 0.219 N2 =
0.248
Calculate the specific gravity if the
molecular weight of air is 28.97 kg/lg-mol
a)
A. 0.981
b)
B. 1.244
c)
C. 1.055
d)
D. 0.542
115.
A bituminous coal has the following
composition:
C= 71.5% H = 5.0% O = 7.0%
N = 1.3% S = 3% Ash = 7.6%
W = 3.4%
Determine the theoretical weight of
Nitrogen in lb/lb of coal
a)
A. 2.870
b)
B. 7.526
c)
C. 2.274
d)
D. 6.233
116.
A gaseous fuel mixture has a molal analysis:
H2 = 14% CH4 = 3% CO =
27%
O2 = 0.6% CO2 = 4.5% N2 =
50.9%
Determine the air-fuel ratio for complete
combustion on molal basis.
a)
A. 2.130
b)
B. 3.230
c)
C. 1.233
d)
D. 1.130
117.
A volumetric analysis of a gas mixture is as
follows:
CO2 : 12%
O2 : 4%
N2 : 80%
CO4 : 4%
What is the percentage of CO2 on a mass
basis?
a)
A. 17.55%
b)
B. 15.55%
c)
C. 12.73%
d)
D. 19.73%
118.
A diesel cycle has a cut off ratio of 2.5 and
expansion ratio of 4. Find the clearance of
cycle.
a)
A. 9.11%
b)
B. 5.55%
c)
C. 11.11%
d)
D. 15.15%
119.
A dual cycle has an initial temperature of
30C. the compression ratio is 6 and the heat
addition at constant volume process is
600kj/kg. if cut off ratio is 2.5, find the
maximum temperature of the cycle.
a)
A. 3638.50 deg C
b)
B. 3365.50 deg C
c)
C. 3565.50 deg C
d)
D. 3965.50 deg C
120.
A three stages air compressor compresses
air from 100kpa to 1000kpa. Find the
intercooler pressure between the first and
second stage.
a)
A. 505.44kpa
b)
B. 108.44kpa
c)
C. 316.23kpa
d)
D. 215.44kpa
121.
A 10—stages air compressor compresses air
from 100kpa to 800kpa. Find the intercooler
pressure between the first and second stage.
a)
A. 282.84 kpa
b)
B. 113.21 kpa
c)
C. 123.11 kpa
d)
D. 333.51 kpa
122.
A 3 stages air compressor compresses air
from 100kpa to 700kpa. Find the intercooler
pressure between 2nd and 3rd stage
a)
A. 365.88 kpa
b)
B. 375.88 kpa
c)
C. 385.88 kpa
d)
D. 395.88 kpa
123.
Carnot cycle a,b,c are connected in series so
that the heat rejected from a will be the heat
added to B an heat rejected from b will be
added to c. each cycle operates between
30degC and 400degC. If heat added to A is
1000kw, find the work output of C.
a)
A. 111.4 kw
b)
B. 549.78 kw
c)
C. 247.53 kw
d)
D. 141.89 kw
124.
Air is compressed adiabatically from
30degC to 100degC. If mass of air being
compressed is 5kg, Find the change of
entropy?
a)
A. 1.039 kj/kg
b)
B. 0.746 kj/kg
c)
C. 0
d)
D. 1.245 kj/kg
125.
Two kilogram of air in a rigid tank changes
its temperature from 32degC to 150degC.
Find the work done during the process.
a)
A. 236
b)
B. 170
c)
C. 195
d)
D. 0
126.
Determine the atmospheric pressure at a
location where barometric reading is
740mm Hg and gravitational acceleration is
g = 9.7m/s^2. Assume the temperature of
mercury to be 10 deg.C at which the density
is 13,570 kg/m^3.
a)
A. 99.45 kpa
b)
B. 97.41 kpa
c)
C. 95.44 Kpa
d)
D. 98.66 Kpa
127.
The barometer of a mountain hiker reads
930mbars at the beginning of a hiking reads
780 mbar at the end. Neglecting the effect of
altitude on local gravitational acceleration,
determine the vertical distance climbed.
Assume g = 9.7 m/s^2.
a)
A. 1275.21 m
b)
B. 1289.00 m
c)
C. 1267.34 m
d)
D. 1583.34 m
128.
The lower half of a 10 m high cylindrical
container is filled with water and upper half
with oil that has SG= 0.85. determine the
pressure difference between the top and
bottom of the cylinder.
a)
A. 90.74 Kpa
b)
B. 92.74 Kpa
c)
C. 83.38 Kpa
d)
D. 98.10 Kpa
129.
An ideal gas at 0.80 atmosphere and 87degC
occupies 0.450 liter. How many moles are
there is the sample? (R=0.0821 literatm/
mole-K)
a)
A. 0.0002 mole
b)
B. 0.0378 mole
c)
C. 0.0122 mole
d)
D. 0.0091 mole
130.
A certain gas at 101.325 Kpa and 10 degC
whose volume is 2.83 m^3 are compressed
into a storage vessel of 0.31m^3 capacity.
Before admission, the storage vessel
contained the gas at a pressure and
temperature of 137.8 Kpa and 26 degC; after
admission the pressure has increased to
1171.8 Kpa. What should be the final
temperature of the gas in the vessel in
kelvin?.
a)
A. 298.0
b)
B. 319.0
c)
C. 180.0
d)
D. 314.2
131.
A superheat steam Rankine cycle has
turbine inlet conditions of 17.5 MPa and 530
degC expands in a turbine to 0.007 Mpa.
The Turbine and pump polytrophic
efficiencies are 0.85 and 0.75 respectively,
pressure losses between pump and turbine
inlet are 1.5 Mpa. What should be the pump
work in Kj/kg?
a)
A. 17.34
b)
B. 27.32
c)
C. 25.32
d)
D. 47.33
132.
In an open feedwater heater for a steam
plant, saturated steam at 7 bar is mixed subcooled
liquid at 7 bar and 25 degC. Just
enough steam is supplied to ensure that the
mixed steam leaving the heater will be
saturated liquid at 7 Bar when heater
efficiency is 95%. Calculate the mass flow
rate of sub-cooled liquid if steam flow rate
is 0.865 kg/s.
a)
A. 2.725 kg/s
b)
B. 3.356 kg/s
c)
C. 2.869 kg/s
d)
D. 3.948 kg/s
133.
A steam condenser receives 10 kg/s of
steam with an enthalpy of 2770 kj/kg.
steam condenses into a liquid and leaves
with an enthalpy of 160 kj/kg. cooling
water passes through the condenser with
temperature increases from 13 DegC to 24
DegC. Calculate the water flow rate in
Kg/s.
a)
A. 583
b)
B. 567
c)
C. 523
d)
D. 528
134.
Steam expands adiabatically in a turbine
from 200 Kpa, 400 DegC to 400 Kpa, 250
DegC. What is the effectiveness of the
process in percent assuming an atmospheric
pressure of 18 DegC. Neglect changes in
kinetic and potential energy.
a)
A. 82
b)
B. 84
c)
C. 79.60
d)
D. 79.46
135.
A heat exchanger was installed purposely to
cool 0.50 kg of gas per second. Molecular
weight is 32 and k = 32. The gas is cooled
from 150 degC to 80 DegC. Water is
available at the rate of 0.30 kg/s and at a
temperature of 5 degC. Calculate the exit
temperature of the water in degC.
a)
A. 44.86
b)
B. 42.88
c)
C. 46.45
d)
D. 40.34
136.
A 350 mm x 450 mm steam engine running
at 280 rpm has an entrance steam condition
of 2 MPa and 230 degC and exit 0.1 Mpa.
The steam consumption is 2000 kg/hr and
mechanical efficiency is 85% if indicated
mean effective pressure is 600 Kpa,
determine brake thermal efficiency.
a)
A. 23,34%
b)
B. 15.25%
c)
C. 14.16%
d)
D. 27.34%
137.
A steam turbine with 85% stage efficiency
receives steam at 7 Mpa and 550 degC and
exhaust as 20 Kpa. Determine the turbine
work.
a)
A. 1,117 Kj/kg
b)
B. 1,182 kj/kg
c)
C. 1,123.34 kj/kg
d)
D. 1,054.95 Kj/kg
138.
A steam turbine with 80% stage efficiency
receives steam at 7 Mpa and 550 DegC and
exhaust as 20 Kpa, determine the quality at
exhaust
a)
A. 96.96%
b)
B. 76.34%
c)
C. 82.34%
d)
D. 91.69%
100 %
