1. ________ is the quality of being plastically plastically elongated. Plasticity o
2. 0.2 kg of air is compressed slowly from 150 kPa and 40 C to 600 kPa, in an adiabatic 3
process. Determine the final volume. 0.0445 m 3.
1 ft-lb is equivalent to ___Joules. 1.356 3
4. 2 m of an ideal gas are compressed from 100 kPa to 200 kPa. As a result of the process, the internal energy of the gas increases i ncreases by 10 kJ, and 140 kJ of heat is transferred to the surroundings. How much work was was done by the gas during the process? -150 kJ 5. A 0.2-m3 tire is filled withh 25oC air until < i>P = 280 kPa. The mass of air in the tire is nearest==0.888 kg 3
6. A 0.2-m rigid conyains steam at 600 kPa and a quality of 0.8. If 1000 kJ of heat are o
added, the final temperature is nearest==670 C 7. A 1.5 cm solid shaft rotates at 1800 rpm. If the allowable torsional shearing stress is 50 Mpa, what power in kW the said shaft can transmit? 6.24 transmit? 6.24 kW 8. A 10 g blocks slides with a velocity of 20 cm/s on a smooth level surface and makes a head on collision with a 30 gram block moving in the opposite direction with a velocity of 10 cm/s. If the collision is perfectly elastic, what is the velocity of the 30-gram block after the collision? - 5 - 5 cm/s 9. A 10 Kg block rests on a smooth surface. If the pulleys are massless and frictionless, the 2
block's initial acceleration is - 10.00 m/s
10. A 10 kg blocks rests on a smooth surface, compute the blocks initial acceleration. 5 2
m/s
3
o
11. A 10 m uninsulated tank contains nitrogen at 2 Mpa and 250 C. The temperature of the o
environmnet surrounding the tank is 35 C. Disregard the mass of the tank. What entropy change do the surroundings experience after a long period of time?==67kj/k 12. A 100 kg weight rests on a 30° inclined plane. Neglecting friction how much pull most one exert to bring the weight up the plane? 50 kg 13. A 120-V electric resistance heater draws 10 A. It operates for 10 min in a rigid volume. Calculate the work done on the air in the volume.==720kJ 14. A 19-foot beam 10 inches wide and 20 inches high supports 1500 lb/ft on two supports 14 feet apart. The right end of the beam extends 2 feet past the support. What is the shearing stress midway between supports? - 2.0 psi
15. A 2.5 in. diameter shaft is 2 ft. long. Its maximum shear stress is 10, 000 psi. What is the angular deflection in degrees? - 0.96
o
16. A 20 lb block is moving along a smooth surface. If the normal force on the surface at A is 10 lb, the velocity is______. 10.6 ft/s 17. A 200kg crate is on top of a 5m-hill. Its potential energy with respect to the bottom of 3
the hill is -- 9.80x10 J 18. A 200kg crate is on top of a 5m-hill. Its potential energy with respect to the bottom of the hill is – is – 9.8e3 J 19. A 200-mm-diameter piston is lowered by increasing the pressure from 100 kPa to 80 0 2
kPa such that the P-V relationship relationship is PV = const. What is the work done on the system 3
if V 1 = 0.1 m ? -18.3 kJ 3
o
20. A 2-m rigid volume contains water at 80 C with a quality of 0.5. Calculate the final o
temperature if 800 kJ of heat are added. 80 C 21. A 30-m long aluminum bar is subjected to a tensile stress of 175 Mpa. Determine the elongation if E = 69116 Mpa. – Mpa. – 76 mm 22. A 35 m x 15 m swimming pool is filled with water to a depth of 3 m. How much heat is required to raise the temperature of the water in the pool from 10oC to 25oC?==99GJ 23. A 5.0 m, ladder leans agains a wall at a point 4.0 m. above the ground. The ladder is uniform and has a mass of 12 kg. Assuming the wall is frictionless and the grounds is not. Determine the horizontal component of the force exerted by the ground on the ladder. – ladder. – 44 N 24. A 56-lb mass rests on a horizontal surface is 20 lb. determine the coefficient of friction. 0.01 o
o
25. A 5-kg block of copper at 100 C is submerged in10 kg of water at 10 C, and after a period of time, equilibrium is established. If the container is insulated, calculate the entropy change of the universe. 0.082 kJ/K 26. A ball is dropped from a height of 60 meters above ground. How long does it take to hit the ground. - 3.5s 27. A ball is dropped from the top of a tower high at the same instant a second ball is thrown upward from the ground. If the two balls meet each other at a point 60 m above the ground, determine the initial velocity of the second ball. – ball. – 35.02m/s 35.02m/s
15. A 2.5 in. diameter shaft is 2 ft. long. Its maximum shear stress is 10, 000 psi. What is the angular deflection in degrees? - 0.96
o
16. A 20 lb block is moving along a smooth surface. If the normal force on the surface at A is 10 lb, the velocity is______. 10.6 ft/s 17. A 200kg crate is on top of a 5m-hill. Its potential energy with respect to the bottom of 3
the hill is -- 9.80x10 J 18. A 200kg crate is on top of a 5m-hill. Its potential energy with respect to the bottom of the hill is – is – 9.8e3 J 19. A 200-mm-diameter piston is lowered by increasing the pressure from 100 kPa to 80 0 2
kPa such that the P-V relationship relationship is PV = const. What is the work done on the system 3
if V 1 = 0.1 m ? -18.3 kJ 3
o
20. A 2-m rigid volume contains water at 80 C with a quality of 0.5. Calculate the final o
temperature if 800 kJ of heat are added. 80 C 21. A 30-m long aluminum bar is subjected to a tensile stress of 175 Mpa. Determine the elongation if E = 69116 Mpa. – Mpa. – 76 mm 22. A 35 m x 15 m swimming pool is filled with water to a depth of 3 m. How much heat is required to raise the temperature of the water in the pool from 10oC to 25oC?==99GJ 23. A 5.0 m, ladder leans agains a wall at a point 4.0 m. above the ground. The ladder is uniform and has a mass of 12 kg. Assuming the wall is frictionless and the grounds is not. Determine the horizontal component of the force exerted by the ground on the ladder. – ladder. – 44 N 24. A 56-lb mass rests on a horizontal surface is 20 lb. determine the coefficient of friction. 0.01 o
o
25. A 5-kg block of copper at 100 C is submerged in10 kg of water at 10 C, and after a period of time, equilibrium is established. If the container is insulated, calculate the entropy change of the universe. 0.082 kJ/K 26. A ball is dropped from a height of 60 meters above ground. How long does it take to hit the ground. - 3.5s 27. A ball is dropped from the top of a tower high at the same instant a second ball is thrown upward from the ground. If the two balls meet each other at a point 60 m above the ground, determine the initial velocity of the second ball. – ball. – 35.02m/s 35.02m/s
o
28. A ball is thrown at an angle of 30 to the horizontal and lands on the top edge of a building 5 m high. If the building is 20 m away, determine the initial velocity of the ball? 20 m/s 29. A ball is thrown at an angle of 45° with horizontal at an initial speed of V A = 10m/s. What is the maximum height it can attain? 2.55 m 30. A ball is thrown horizontally from A with the speed of v A = 6 m/s. If it strikes the ground in t = 1.52 s, the height h is - 11.33 m 31. A ball is thrown horizontally from A with the speed of v A= 6 m/s. If it strikes the ground in t = 1.52 s, the height h is – is – 11.33m 32. A ball is thrown vertically into the air at 120 m/s. After 3 seconds, another ball is thrown vertically. What is the velocity must the second ball have to pass the first ball at 100 m from the ground? 105.89 m/s 33. A ball is thrown vertically into the air at 120 m/s. m/ s. After 3 seconds, another ball is thrown vertically. What is the velocity must the second ball have to pass the first ball at 100 m from the ground? - 105.89 m/s 34. A ballon is fiiled with pure oxygen at 10oC. The ballon is released from the bottom of a water-filled testing pool and floats 30 m to the water surface (where the atmospheric pressure is standard). The initial (submerged) volume o fthe ballon is 3000 cm3. The temperature is 25oC at the surface o fthe water, and the water temperature at the bottom of the pool is 10 oC. What is the volume of the ballon at the surface after it has volume into thermal equilibrium with the surroundings?==12300 35. A bell jar 200 mm in diameter sits on a flat plate and is evacuated until a vacuum of 720 mmHg exists. The local barometer reads 760 mmHg. Estimate the force required to lift the jar off the plate. Neglect the weight of the jar. --3000 N o
36. A box is being pulled by a force of 20 lb exerted in a rope inclined 30 with horizontal. What is the effective component of the force pulling the box? 17.32 lbs 37. A box is being pulled by a force of 20 lb exerted in a rope inclined 30° with horizontal. What is the effective component of the force pulling the box? - 17.32 lbs 38. A boy on the beach holds a spherical ballon filled with air. At 10:00 a.m., the o
temperature on the beach is 20 C and the ballon has a diameter of 30 cm. Two hours later, the ballon diameter is 30.5 cm. Assuming that the air is an ideal gas and that no air was lost or added, what is the temperature on the beach at noon?==35C
39. A cable 200 m long weighs 50 N/m and is supported from two points at the same elevation. Determine the required sag if the maximum tension that the cable can carry shall not exceed 8000N. 30 m 40. A car moving at 70 kph has a mass of 1700 kg. What force is necessary to decelerate it at 2
a rate of 40 cm/s - 680 N 41. A car tire is 30 inches in diameter. How fast in rpm does the wheel turns on the axle when the automobile maintains a speed of 30 mph? 336 rpm 42. A Carnot cycle is a cycle of special interest because:== It provides the maximum efficiency for any cycle. 43. A Carnot cycle refrigerator operates between -11oC and 22oC. What is the coefficient of performance?==7.9 44. A Carnot engine operates between reservoirs at 20 and 200oC. If 10 kW of power id produced, find the rejected heat rate.== 16.3 kJ/s o
45. A Carnot engine receives 100 kJ of heat from a hot reservoir at 370 C and rejects 37 kJ o
of heat. Determine the temperature of the cold reservoir.== -35 C 46. A Carnot engine requires 35 kJ/s from the hot source. The engine produces 15 kW of power and the temperature of the sink is 26 oC. What is the temperature of the hot source in oC?==250.18 47. A Carnot refrigerating system recieves haet from a cold reservor at 0 o. The power input is 1750 W per ton of refrigeration. Find the system's coefficient of performance.==2 o
48. A Carnot refrigerator requires 10 kW to remove 20 kJ/s from a 20 C reservoir. What isT H? 440 K 49. A closed gaseous system undergoes a reversible process during which 25 Btu are rejected, the volume changing from 5 ft3 to 2 ft3, and the pressure remains constance at 50 psia. Find the change of internal energy.== 2.76 Btu 50. A closed rigid vessel contains 40% liquid water and 60% water vapor by volume. The o
liquid-vapor mixture is in equilibrium at 150 C. What I sthe quality of the mixture? 4.15 -3
x 10
51. A closed vessel contains air at a pressure of 160 kN/m2 gauge and temperature of 30oC. The air is heated at constant volume to 60oC with the atmospheric pressure of 759 mm Hg. What is the final gauge pressure?==186 2
52. A cubic meter of a liquid has a weight of 9800 N at a location where g = 9.79 m/s . What 2
is its weight at a location where g = 9.83 m/s ? 9840 N
53. A cylinder fitted with a frictionless piston contains an ideal gas at temperature T and pressure p. The gas expands isothermally and reversibly until the pressure is p/3. Which statement is true regarding the work done by the gas during expansion?== It is equal to the heat absorted by the gas. 54. A cylinder of diameter 1.0 cm at 30°C is to be slide into a hole on a steel plate. The hole has a diameter of 0.99970 cm at 30°C. To what temperature the plate must be heated? -5
Coefficient of linear expansion for steel is 1.2 x 10 per °C -
55°C
o
55. A cylinder of diameter 1.0 cm at 30 C is to be slide into a hole on a steel plate. The hole o
has a diameter of 0.99970 cm at 30 C. To what temperature the plate must be heated? -5
o
o
Coefficient of linear expansion for steel is 1.2 x 10 per C. -- 55 C o
56. A cylinder of diameter 1.0 cm at 30 C is to be slide into a hole on a steel plate. The hole o
has a diameter of 0.99970 cm at 30 C. To what temperature the plate must be heated? -5
o
o
Coefficient of linear expansion for steel is 1.2 x 10 per C. 55 C 57. A force of 100N acts at point A. the value of F AC is – 141.4 kN 58. A gage pressure of 400 kPa acting on a 4-cm-diameter piston is resisted by a spring with a spring constant of 800 N/m. How much is the spring compressed? Neglect the piston weight and friction. 63 cm 59. A gage pressure of 400 Kpa acting on a 4-cm-diameter piston is resisted by an 800-N/m spring. How much is the spring compressed?==0.628m o
3
60. A gas with a molecule weight of 55 initially at 2 Mpa, 200 , and 0.5m expands in 1.35
accordance with the relation pu
= C to 0.2 Mpa. Determine the work for the
expansion process.==1,3MJ 61. A gasoline engine drives a small generator that is to supply sufficient electrical energy for a motor home. What is the minimum horsepower engine that would be necessary if a maximum of 200 A is anticipated from the 12-V system?==3.2hp 62. A general system of forces and couple moments acting on a rigid body can be reduced to a ____. single force and a single moment. 63. A golf ball leaves the golf club at an angle of 60° above the horizontal reference with a velocity of 25 m/s. How high does it go? - 23.89 m 64. A group of 50 persons attend a secret meeting in room which is 12 m wide by 10 m long and a ceiling height 0f 3 m. The room is completely sealed off and insulated. Each persons gives off 150 kCal per hour of heat and occupies a volume of 0.20 m3. The room has an initial pressure of 101.3 kPa and temperature of 16oC. Calculate the room temperature aqfter 10 munites. User R = 0.287 kJ/kg-K and Cv = 0.171 kCal/kg-K==33.1
o
o
65. A heat engine is operated between temperature limits of 137 C and 260 C. Engline is supplied with 14,142 kJ/kwh. Find the cannot cycle efficiency in percent. 67.56 o
o
66. A heat pump is maintain a house at 20 C when the outside air is at -25 C. It is determined that 1800 kJ is required each minute to accomplish this. Calculate the minimum power required. 4.61 kW o
o
67. A heat pump is to provide 2000 kJ/hr a house maintaned at 20 C. If is -20 C outside, what is the minimum power requirement? 273 kJ/hr 68. A heat pump using R134a as the refrigerant provides 80 MJ/h to a building.The cycle operates between pressures of 1000 and 200 kPa. Assuming an ideal cycle compressor horsepower is nearest==3.28 69. A household window air conditioner has an nergy efficiency rating of 7.5 kJ/W.h. What is the coefficient of performance for the unit? 2 .1 70. A liquid boils when its vapor pressure is equal to. the absolute pressure. 71. A load of 100 lb is hung from the middle of a rope, which is stretched between two rigid walls 30 ft apart. Due to the load, the rope sags 4 ft in the middle. Determine the tension in the rope. – 194lbs 72. A man can exert a maximum pull of 1,000 N but wishes to lift a new stone door for his cave weighing 20,000 N. If the uses a lever how much closer must the fulcrum be to the stone than to his hand? 20 times nearer 73. A man dropped a stone into a well. Four seconds later the sound of a water splash is heard. Assuming sound travels at a speed of 330 m/s, determine how deep is the well? 70.34 m 74. A man dropped a stone into a well. Four seconds later the sound of a water splash is heard. Assuming sound travels at a speed of 330 m/s, determine how deep is the well? 70.34 m o
75. A nozzle accelerates steam at 120 kPa and 200 C from 20 m/s to the atmosphere. If it is 85 percent efficient, the exiting velocity is nearest. 230 m/s 76. A nozzle accelerates steam at 4 Mpa and 500oC to 1 Mpa and 300oC. If V1 = 20 m/s, the exiting velocity i s nearest. Calculate the mass flow rate at the nozzle exit of above problem.==1.8 o
o
77. A nozzle accelerates steam at 4 Mpa and 500 C to 1 Mpa and 300 C. If V 1 = 20 m/s, the exiting velocity is nearest. Calculate the mass flow rate at the nozzle exit of above problem. 1.8 kg/s o
o
78. A nozzle accelerates steam at 4 Mpa and 500 C to 1 Mpa and 300 C. If V 1 = 20 m/s, the exiting velocity is nearest. 890 m/s
79. A paddle wheel and electric heater operate in asystem. If the torque i s 200 N.m, the rotational speed is 400 rpm, the voltage is 20 V, and the amperage is 10 A, what is the rate of doing work? -2040 W 80. A particle P is travelling around a circular path such that at the instant considered, the 2
speed is 3m.s and increasing at 4m/s . The magnitude of the particle's acceleration at 2
that instant is - 5.00 m/s
81. A person carries 200-N weight from one end of a hall to the other 100 m away. How much work has the person done? 0 J 82. A piston allows air to expand from 6 MPA to 200 kPa. The initial volume and 3
o
temperature are 500 cm and 800 C. If the temperature is held constant, calculate the entropy change.== 9.51 kJ/K 83. A piston-cylinder arrangement provides a constant pressure of 800 kPa on steam which 3
has an initial quality of 0.95 and an initial volume of 1200 cm . Determine the heat o
transfer necessary to raise the temperature to 400 C.==127kJ 84. A pressure gage registers 50 psig in a region where the barometer is 14.25 psia. Find the absolute pressure in psia.== 64.25 psia 85. A proposed power cycle is designed to operate between temperature reservoirs of 900 o
and 20 C. It is supposed to produce 43 hp from the 2500 kJ of energy extracted each minute. Is the proposal feasible? No 86. A pump is to increase the pressure of 200 kg/s of water by 4 MPa. The water enterd through a 20-cm diameter pipe and exits through a 12-cm-diameter pipe. Calculate the minimum horsepower required to operate the pump.==107KW 87. A Rankine cycle operates between 10 Mpa and 20 kPa. If the high temperature of the o
steam is 600 C, the heat input is nearest. 3375 kJ/kg 88. A Rankine cycle operates between 10 Mpa and 20 kPa. If the high temperature of the o
steam is 600 C, the heat input is nearest. The steam in the Rankine cycle of above o
problem is reheated at 4 Mpa to 600 C. The total heat input is nearest. 3745 kJ/kg 89. A Rankine cycle operates between 10 Mpa and 20 kPa. If the high temperature of the o
steam is 600 C, the heat input is nearest. The turbine output of the Rankine cycle of above problem is nearest. If the mass Flux is 2400 kg/min, the pump power requirement in the Rankine cycle of above problem is nearest. 1260 kW 90. A Rankine cycle operates between 10 Mpa and 20 kPa. If the high temperature of the steam is 600oC, the heat input is nearest. The turbine output of the Rankine cycle of above problem is nearest==1350 kJ/kg 91. A Rankine steam cycle operates between the pressure limits of 600 kPa and 10 kPa. The turbine inlet temperature is 300oC. The liquid water leaving the condenser
is saturated. (The enthalpies of the steam at the various points on the cycle are shown in the illustration.) What is the thermal efficiency of the cycle?==0.25 92. A rectangular system is said to be right-handed if - the thumb of the right hand points in the direction of the positive z axis when the right hand fingers are curled about this axis and directed from the +x towards the +y axis. 93. A resultant couple moment is simply the vector sum of all the couple moments of the system. - A couple moment causes different effect of rotation on a body when it is applied at different point. 94. A reversible thermodynamic system is made to follow the Carnot cycle between the o
o
temperature limits of 300 C and 75 C. 300 kW of heat are supplied per cycle to the system. What is the change in entropy during the heat addition? 0.52 kW/K 95. A rigid vessel with a volume of 10 m3 contains a water-vapor mixture at 400 kPa at 60 percent quality. The pressure is lowered to 300 kPa by cooling the vessel. Find mg at state 2.==16.5KG 3
96. A rigid, insulated 4-m volume is divided in half by a membrane. One chamber is pressurized with air to 100 kPa and the other i s completely evacuated. The membrane is ruptured and after a period of time equilibrium is restored. The entropy change of the air is nearest --0.473 kJ/K 97. A single bolt is used to lap joint to steel bars together. Tensile force on the bars is 20,000 N. Determine the diameter of the bolt required if the allowable shearing stress on it is 70 MPa. 19mm 98. A solid shaft 2.0 m long is transmitting 27 kN-m torque. If the shear modulus of the shaft material is 85 Gpa and the allowable shearing stress is 70 Mpa, determine the angle of o
twist between the two ends of the shaft. - 1.52
99. A steam coil operating at steady state recieves 30 kg/ min of steam with an enthalpyof 2900 kJ/kg. If the steam leaves with anenthalpy of 1600 kJ/kg, what is the rate of heat transfer from the coil? 39 000 kJ/min 100.
A steam condenser receives 10kg per second of steam with an enthalpy of 2,570
kJ/kg. Steam condenses into liquid and leaves with an enthalpy of 160 kJ/kg. Cooling o
o
water passes through the condenser with temperature increase from 13 C to 24 C. Calculate the cooling water flowrate in kg/s. 523 101.
A steam power plant is designed to operate on a Rankine cycle with a condenser
pressure of 100 kPa and boiler outlet temperature of 500 oC.If the pump outlet pressure is 2 Mpa,calculate the ideal turbine work output.
The steam passing
through the turbine of the power cycle of above problem is reheated at 800 kPa to 500oC. The thermal efficiency of the resulting reheat Rankine cycle is nearest==26.2% 102.
A steam power plant is designed to operate on a Rankine cycle with a condenser o
pressure of 100 kPa and boiler outlet temperature of 500 C.If the pump outlet pressure is 2 Mpa,calculate the ideal turbine work output. The boiler requirement of the cycle of above problem is nearest==3050kj/kg 103.
A steam power plant is designed to operate on a Rankine cycle with a condenser o
pressure of 100 kPa and boiler outlet temperature of 500 C.If the pump outlet pressure is 2 Mpa,calculate the ideal turbine work output.==0.25 104.
A steam power plant is designed to operate on a Rankine cycle with a condenser o
pressure of 100 kPa and boiler outlet temperature of 500 C.If the pump outlet pressure is 2 Mpa,calculate the ideal turbine work output.==764kj/kg 105.
A steel wire is 4.0 m long and and 2 mm in diameter. How much is it elongated
by a suspended body of mass 20 kg? Young's modulus for steel is 196,000 MPa - 1.274 mm 106.
A stone is thrown vertically upward and returns to earth in 10 sec. What was its
initial velocity? - 161 ft/s 107.
A stone with a mass of 0.2 kg is tied to one of a string 1.2 m long and is whirled
around in a vertical circle. If the breaking strength of the string in tension is 90 N, what is the angular velocity at which the cord will break? - 36.57 rpm 108.
A stop is located 20 mm above the piston shown in . If the mass of the
frictionless piston is 64 kg, what work must the air do on the piston to increase the pressure in the cylinder to 500 kPa? 53 J 109.
A substance whose properties are uniform through-out a sample is referred to
as. a pure substance 110.
A tank contains 80 ft3 of air at a pressure of 350 psi. If the air is
cooled until its pressure and temperature decrease to 200 psi and 70 oF respectively, what is the decrease in internal energy?== -5507 111.
A thief escapes and boarded on a truck and traveled at a constant speed of 55
kph. Two hours later the truck left, a policeman riding on a motorbike pursued the fugitive at a constant speed of 80 kph. How long did it take the policeman to catch up the criminal. 4.4 hrs
112.
A thin hollow sphere of raduis 300 mm and thickness 2.5 m is subjected to an
internal pressure. Determine the internal pressure if the tensile stress of an element in the sphere is 360 kPa. – 6kPa 113.
A train changes its speed uniformly from 60 mph to 30 mph in a distance of 1500 2
ft. What is its acceleration? - -1.94 ft/s
3
114.
A turbine at a hydroelctric plant accepts 20 m /s of water at a gage pressure of
300 kPa and discharge it to the atmosphere. Determine the maximum power output. 115.
A vertical circular cylinder holds 1 cm of liquid water and 100 cm of vapor. If P =
200 kPa, the quality is nearest: 10.7 116.
A vessel with a volume of 1 m3 contains liquid water and water
vapor in equilibrium at 600 kPa. The li quid water has a mass of 1 kg. Calculate the mass of the water vapor. Properties of liquid water and water vapor at 600 kPa: V1 = 0.001101 m3/kg Vg = 0.3157 m3/kg==3.16kg o
117.
A water temperature rise of 18 F in the water cooled condenser is equivalent o
o
in C to: 10 C 118.
o
After the piston hits the stops in if P1 =400 kPa and T 1= 400 C, what is T 2 when 2
the 0.2-m piston hits the stops? How much additional heat is released before P = 100 kPa? 1580 kJ 119.
Air enters a nozzle with P1 = 585 kPa, T1
= 195oC, and V1 = 100 m/s. If the air exits to the atmosphere where the pressure is 85 kPa, find exiting velodity, assuming an adiabatic process.== 835 m/s 120.
o
Air enters an insulated compressor at 100 kPa and 20 C and exits at 800 kPa. o
Estimate the exiting temperature. 258 C 121.
Air enters the compressor of an ideal gas-refrigeration cycle at 10oC
and 80 kPa. If the maximum and minimum temperature are 250oC and 50oC, the compressor work is nearest:
The COP for the refrigeration cycle of above problem is nearest:==1.18 122.
Air enters the compressor of an ideal gas-refrigeration cycle at 10oC
and 80 kPa. If the maximum and minimum temperature are 250oC and 50oC, the compressor work is nearest:
The pressure ratio across the compressor in the cycle of above problem is nearest:8.6 123.
o
Air enters the compressor of an ideal gas-refrigeration cycle at 10 C and 80 kPa. o
o
If the maximum and minimum temperature are 250 C and -50 C, the compressor work is nearest:==2400kj/kg
124.
Air is commpressed isentropically such that its pressure is increased by 50%. The o
o
initial temperature is 70 C. What is the final temperature. 110 C o
125.
Air is compressed adiabatically from 100 kPa and 20 C to 800 kPa. The o
temperature T 2 is nearest. 260 C o
126.
o
Air is compressed from 100 kPa and 40 C to 1500 kPa and 130 C in a sateady-
flow operation. During the compression process, each kilogram of air loses 90 kJ as heat 3
to the environment. Air is discharged at the rate of 10 m /min. What power is required to drive the compressor? 391 kW 127.
Air is compressed in a cylinder such that the volume changes from 0.2 to 0.02 3
m . The initial pressure is 200 kPa. If the pressure is constant, the work is nearest ---36 kJ 128.
Air undergoes a three-process cycle. Find the net work done for 2 kg of air if the
processe are 1 --> 2: constant-pressure expansion 2 --> 3: constant volume 3 -->1: constant-temperature compression o
o
The necessary information is T 1 = 100 C, T 2 = 600 C, and P1 = 200 kPa. --105 kJ 129.
All real gases deviate to some extent from the ideal behavior described by the
equation pV = mRT. For which o fthe following condinions are the deviations smallest? high temperatures and low pressures 130.
An air bubble rises from the bottom of a well where the tempeture is
25oC, to the surface where the temperature is 27oC. Find the percent increase in the volume of the bubble if the depth of the well is 5 m. Atmospheric pressure is 101,528 Pascals.==0.493 131.
An automobile that has a gas mileage of 13 km/L is traveling at 100 km/h. At this
speed essentially all the power produced by the engine is used to overcome air drag. If 1
2
the air drag force is given /2 pV AC Ddetermine the thermal efficiency of the engine at 2
this speed using projected area A = 3 m , drag coefficient C D = 0.28, and heating value of 3
gasoline 9000 kJ/kg. Gasoline has a density of 740 kg/m .==0.519 132.
o
o
An electric heater is to heat 11 kg of oil per min. from 4.5 C to 65.5 C. Specific o
heat of the oil is 2.1 J/gm- C. How many watts should this heater consume? 23,442 W 133.
An electrical voltage of 110 V is applied across a resistor providing a current of
12 A through the resistor. The work done during a period of 10 min is nearest==792mJ 134.
An elevator weighs 1000 pounds and is supported by a 5/16 inch diameter cable,
1500 feet long. When the elevator carries a 1500 lb, the cable elongates 6 inches more. 7
What is the modulus of elasticity of the cable? 5.87 x 10 psi
135.
An elevator weighs 1000 pounds and is supported by a 5/16 inch diameter
cable, 1500 feet long. When the elevator carries a 1500 lb, the cable elongates 6 inches 7
more. What is the modulus of elasticity of the cable? 5.87 x 10 psi 136.
o
o
An engine operates on 100 C geothermal water. It exhausts to a 20 C stream. Its
maximum efficiency is nearest--0.21 137.
o
An ideal gas at a gage pressure of 0.3 Mpa and 25 C is heated in a closed o
container to 75 C. What is the final? 0.47 Mpa 138.
An ideal gas has a ratio of specific heats of 1.4 and a specific heat at constant
pressure of 1100 kJ/kg.K. The gas flows through a partially closed valve and expriences a o
pressure drop from 700 kPa to 150 kPa. If the temperature before the valves is 100 C, o
what i sthe temperature after the valve? -33 C 139.
An ideal gas has a ratio of specific heats of 1.4 and a specific heat at constant
pressure of 1100 kJ/kg.K. The gas flows through a partially closed valve and expriences a pressure drop from 700 kPa to 150 kPa. If the temperature before the valves is 100oC, what i sthe temperature after the valve?==100 C 140.
o
o
An ideal gas is 45 psig and 80 F is heated in a closed container to 130 F. What is
the final pressure? 65 psia 141.
An ideal Rankinecycle consists of which of the following? two constant pressure
and two isentropic processes 142.
An ideal refrigeration cycle operates between a low temperature of -
12oC and a high pressure of 800 kPa. If the mass flow rate is 2 kg/s of R134a, the compressor power requirement is nearest:==60kw 143.
o
An ideal refrigeration cycle operates between a low temperature of - 12 C and a
high pressure of 800 kPa. If the mass flow rate is 2 kg/s of R134a, the compressor power requirement is nearest: The quality of the refrigerant of above problem entering the evaporator is nearest: 29% 144.
o
An ideal refrigeration cycle operates between a low temperature of - 12 C and a
high pressure of 800 kPa. If the mass flow rate is 2 kg/s of R134a, the compressor power requirement is nearest: The COP of the cycle of above problem, when used as a refrigerant , is nearest: --4.8 145.
o
An ideal refrigeration cycle operates between a low temperature of - 12 C and a
high pressure of 800 kPa. If the mass flow rate is 2 kg/s of R134a, the compressor power requirement is nearest: How much heat could the cycle of above problem supply? 1270 MJ/hr 146.
An ideal vapor refrigeration cycle utilizes R134a as the working fluid between o
saturation temperatures of -28 and 40 C.For a flow of 0.6 kg/s, determine the rate of refrigeration. 74.5kJ/s
147.
An inventor claims a thermal engine operates between ocean layers at 27 and
10oC. It produces 10 kW and discharges 9900 kJ/min. Such an engine is IMPOSSIBLE 148.
An iron column of annular cross-section has an outer diameter of 200 mm and is
subjected to a force of 75 kN. Find the thickness of the wall if the allowable compressive stress is 10 Mpa. 12.75mm 149.
An iron steam pipe is 200 ft long at
0o
C. What will be its increase in length when
0o
heated to 10 C? Coefficient of linear expansion is 10 x 1
0-6
o
per C. – 0.20 ft
150.
An isentropic process isAdiabatic but may not be reversible
151.
An isosceles traingle ha s a 10 cm base and a 10 cm altitude. Determine the
moment of inertia of the triangular area relative to a line parallel to the base and 4
through the upper vertex in cm . 2,500 cm
4 o
152.
An oxygen cylinder of volume 2.3 ft 3 has a pressure of 2200 psig and is at 70 F.
Determine the mass of oxygen in the cylinder. 28.66 lbs 153.
As shown below, the total horizontal component of 400N force is -> 400N cos o
30 154.
Assume 8 lb of a substance receive 240 Btu of heat at constant volume and o
undergo a temperature change of 150 F. Determine the average specific heat of the o
substance during the process. 0.2 Btu/lb F 155.
Assume the wall thickness to be one-tenth of the outside diameter. – 112.4 mm
156.
Assuming compression is according to the law PV = constant. Calculate the initial
volu8me of gas at a pressure of 2 bar which will occupy a volume of 6 m3 3
when it is compressed to a pressure of 42 bar.==126 m 157.
At a given instant, blocks A and B have the motion shown. The acceleration of
block B with respect to A is – none of these 158.
At the start of compression in an air-standard Otto cycle with a compression o
ratio of 10, air is at 100 kPa and 40 C. At heat addition of 2800 kJ/kg is made. Calculate the thermal efficiency.==0.6 159.
Calculate the force necessary to accelerate a 900-kg rocket vertically upward at 2
the rate of 30 m/s . 35.8 kN 160. Calculate the maximum power output of an engine operating between 600 and o 20 C if the heat input is 100 kJ/s.==66.4kW 161. Calculate the power developed by the 100 N which acts on the 10 Kg block. The block has a speed of 2 m/s. – 200 W
162.
Calculate the power developed by the 100 N which acts on the 10 Kg block. The
block has a speed of 2 m/s. – 200W 163.
Calculate the power needed to raise the pressure of liquid water 4 Mpa
assuming the temperature remains constant and the mass flux is 5 kg/s.==20kW o
164.
Calculate the power required to compress 10 kg/s of air from 1 atm and 37 C to o
2 atm and 707 C. For low pressure air,. 7330 kW 165.
Calculate the quantity of heat to be tranferred to 2.25 kg of brss to raise its
temperature from 20oC to 240oC taking the specific heat of the brass as 0.394 kJ/kg -K.==195.03kJ 166.
Calculate the specific volume of water at 221oC if the quality is 85 3
percent.==0.072m /kg 3
167.
Calculate the weight of a body that occupies 200 m if its specific volume is 10 3
m /kg. 196 N 168.
Calculate the work needed to expand a piston in a cylinder at a constant
pressure if saturated liquid water is completely vaporized at 200oC.==196kj/kg 169.
Convention heat transfer involves both:== conduction and advection
170.
Convert 178 kPa gage of pressure to abolute millimeters of mercury ( phg =
13.6 pwater). 2080 mm 171.
Convert 200 kPa gage to absolute millimeters of mercury ( pHg = 13.6 pwater). 1500
mm 172.
Determine the abscissa of the centroid for the shadded area as shown. 3.5
173.
Determine the average constant pressure specific heat of steam at 10 kPa and
45.8oC. Note: From steam table, at 47.7oC, h = 2588.1 kJ/kg and at 43.8oC, h = 2581.1 kJ/kg.== 1.79 kJ/kgoC 174.
Determine the average Cp value in kJ/kg-K of heat is necessary to raise the
temperature from 300 K to 800 K making the pressure constant.==1.044 175.
Determine the change in enthalpy per lb mass of nitrogen gas as its temperature o
o
o
changes from 500 F to 200 F. ( Cpm R )== -74.49 Btu/lbm 176.
Determine the diameter of a steel rod that will carry a tensile load of 50,000 kg
at a stress of 1400 kg per square centimetre - 6.74 cm 177.
Determine the force in Newtons required to produce an acceleration of 0.30 2
m/s on a 0.05 kg mass. 0.015 178.
Determine the force required to punch a 1/2 inch hole on a 3/8 thick plate if the
ultimate shearing strength of the plate is 50,000 psi. - 23, 562 lbs
179.
Determine the load capacity in kN on a 25 mm diameter x 1200 mm long steel
shaft if its maximum elongation shall not exceed 1 mm. Assume E = 200, 000 Mpa. 81.8 kN 180.
Determine the load capacity in kN on a 25 mm diameter x 1200 mm long steel
shaft if its maximum elongation shall not exceed 1 mm. Assume E = 200, 000 Mpa. - 81.8 kN 181.
Determine the maximum shear of the beam loaded as shown. - 350 kN
182.
Determine the maximum shear of the beam loaded as shown. 350kN
183.
Determine the maximum thickness of metal plate in which a 7.5 cm diameter
hole can be punched, if the plate has an ultimate shearing strength of 4245 kg per square centimeter and the punch can exert a maximum force of 200 metric tons. – 2.0 cm 184.
Determine the moment of inertia of the T-section as shown about its centroidal
axis parallel to the base. - 10094.31 185.
Determine the outside diameter of a hollow steel tube that will carry a tensile
load of 500 kN at a stress of 140 Mpa. Assume the wall thickness to be one-tenth of the outside diameter. 112.4 mm 186.
Determine the work done by the force when it is subjected to the
displacement indicated. 5.00 J o
187.
Determine T 2 in the Brayton cycle of . 258 C
188.
During a process, 30 J of of work are done by a closed stationary system on its
surroundings. The internal energy of the system decreases by 40 J. What is the heat transfer?== 10 J released into the surroundings 189.
During steady-state operation, the condenser of a steam-power plant receives 7
kg/s of 0.1 Mpa steam. Superheated steam enters the condenser at a temperature of o
900C. Saturated cooling water exist the condenser at 100 . At what rate is heat transferred in the condenser?==27.8MW 190.
2
During the stress strain test, the unit deformation at a stress of 35 MN/m was -6
2
-6
observed to be 167 x 10 mm and at a stress of 140 MN/m it was 667 x 10 mm. If the 2
5
2
proportional limit was MN/m , what is the modulus of elasticity? - 2.1 x 10 N/mm 191.
Engineering mechanics is formulated on the basis of Newton's - Three Laws of
Motion
192.
Engineering thermodynamics does not include. utilization of energy
193.
Estimate Cp for steam at 4 MPa and 350oC.==
2.53 kJ/kg 194.
Estimate the difference in density between the inside and outside of a house in
the winter when P = 100 kPa, Tinside = 20oC, and Toutside = 20oC. (Would you expect any tendency for air exchange due to this difference?)== 0.19 kg/m3 195.
Estimate the difference in density between the inside and outside of a house in o
o
the winter when P = 100 kPa and T inside = 20 C and T outside = -20 C. (This difference leads to air exchange between the inside and outside) --0.188 kg/m
3
o
196.
Estimate the enthalpy of steam at 288 C and 2 Mpa.==2994kj/kg
197.
Estimate the equilibrium temperature if 20 kg of copper at 0oC and
10 L of water at 30oC are placed in an insulated container.==25.4 198.
Estimate the pressure of nitrogen at a temperatue of 220 K and a specific volume 3
of 0.04 m /kg using the compressibility factor. 1600 kPa 199.
Estimate the pressure of nitrogen at a temperatue of 220 K and a specific volume
of 0.04 m3/kg using the compressibility factor.==1600kpa 200.
Estimate the temperature of 2 kg of air contained in a 40 L volume at 2
MPa.==155k 201.
Estimate the tempeture of 2 kg of air contained in a 40-L volume at 2
Mpa==160K 202.
Estimate the volume occupied by 10 kg of water at 200 oC and 2
Mpa.==9.4L o
o
203.
Estimate C p for steam at 4 MPa and 350 C. 2.48 kJ/kg C
204.
F in unit vector notation in figure below is -> -100i N
205.
Find the dot product of the two vectors P and Q. P = {3 i + 2 j + 3 k } m; Q. = {-2 i +
2 j + 4 k } m -> 10 m 206.
2
Find the enthalpy of 1 kg of wet saturated steam at a pressure of 0.20 bar and
dryness fraction of 0.20 bar, h f = 251 kJ/kg, hfg= 2358 kJ/kg -- 2255.30 kJ/kg 207.
o
Find the mass of air in the volume shown, if T = 20 C and the frictionless piston
has a mass of 75 kg. 0.0016 kg 208.
Find the maximum outlet velocity for an air nozzle that operates between 400
and 100 kPa if T1 =27oC.==440 m/s 209.
Find the mimimum work input required by an air compressor if
P1 = 100 kPa, T1 =27o, and P2= 800 kPa.== 243 kJ/kg
210.
Find the quality of steam at 120oC if the vapor occupies 1200 L and
the liquid occupies 2 L.==0.42 o
3
211.
Find the volume occupied by 4 kg of 200 C steam. 0.410 m
212.
Find the work if air expands from 0.2 m3 to 0.8 m3
while the pressure in kPa is P = 0.2 + 0.4V.== 0.24 kJ 213.
Find the work needed to compress 2 kg of air in an insulated cylinder from 100 o
to 600 kPa if T 1 = 20 C. -281 kJ 214.
find the work needed to isentropically compress 2 kg of air in a cylinder at 400 o
kPa and 400 C to 2 MPa.. 563 kJ o
215.
o
Five kilograms of copper at 200 C is 20 kilograms of water at 10 C in an insulated
container. After time passes, the temperature will be nearest. 14
o
3
216.
o
Five kilograms of steam occupy a volume of 10 m . If the temperature is 86 C,
the quality and the pressure are nearest. 0.72, 61 kPa 217.
For a particle in space in static equilibrium, ___ equations can be used. – 3
218.
For every gas there is a particular temperature above which the properties o fthe
gas cannot be distinguished from properties of a liquid no matter how great the pressure. This temperature is known as the==critical temperature 219.
Four kilograms of air expand in an insulated cylinder from 500 kPa and
2277oC to 20 kPa. What is the work output?== 863 kJ 220.
Fr can be determined by - Cosine Law
221.
Frames are different as compared to trusses since they have _______. at least
one multiforce member 222.
Frames are different as compared to trusses since they have _______. at least
one multiforce member 223.
From the figure as shown, determine the total elongation of the composite body
carrying a tensile load of 5 kN. Assume E1 = 10 Mpa and E2 = 15 Mpa. 118mm o
224.
Gas initailly at 1 Mpa and 150 C receives7.2 MJ of work while 1.5 kW of heat are
removed from the system. Calculate the internal energy change for the system over a period of an hour. 1.8 MJ 225.
Given the a - t graph. If v = 6m/s when t = 0, calculate the time t needed to stop
the particle. – 16 s 226. 227.
Given the s - t graph. Calculate the particle's velocity when t = 1s. 0.5 m/s Given the v - t graph. Calculate the particle's acceleration when t = 3s. - 5 2
m/s 228.
2
Given: the v-t graph, the acceleration of the particle when t= 3s is -- -5.00 m/s
229.
Heat can be transferred by conduction through:==all of these
230.
Heat is added to a fixed 0.15-m volume of steam initially at a pressure of 400
3
o
kPa and a quality of 0.5. Estimate the final temperature if 800 kJ of heat is added. 300 C 3
231.
How much heat must be added to a 0.3-m rigid volume containing water at o
o
200 C in order that the final temperature is raised to 800 C? The initial pressure is 1 Mpa.==1505kJ 232.
If = 0.2 kg/s for the cycle of.==5.2cm
233.
If 6 liters of a gas at a pressure of 100 kPaa are compressed reversibly according 2
to PV = C, until the volume becomes 2 liters. Find the final pressure. 900 kPa 2
234.
If a = (2t) m/s , where t is in seconds, calculate the particle's velocity when t = 2s.
When t = 0, Vo = 2m/s. – 6m/s 3
235.
If a particle's position is given by the expression x(t) = 3.4t - 5.4t meters, what is 2
the acceleration of the particle after t = 5 seconds? 102 m/s
3
236.
If a particle's position is given by the expression x(t) = 3.4t - 5.4t meters, what is 2
the acceleration of the particle after t = 5 seconds? 102 m/s 237.
If an deal regenerator is added to the cycle, the temperature entering the burner
is: ==T4 238.
If expressed in Cartesian vector form, F1 is - (2.50 i + 3.54 j + 2.50 k) kN
239.
If s = (4t ) m, calculate the particle's acceleration at t = 2s. - 8 m/s
240.
If T1 27, Estimate T2 assuming constant specific heats?==430
2
2
c 241.
If the cable has a tension of 3 N, determine the acceleration of block B. 8.31 2
m/s ↓ 242.
If the cable has a tension of 3 N, determine the acceleration of block B. 8.31 2
m/s ↓ down 243.
o
o
If the magnitude of F is 80N, a = 60 and y = 45 , the magnitude of its component
is - Fy = 40.0N, Fz = 56.6N, Fx = 40.0N 244.
If the numbers of unknown forces is more than the equations that can be used,
the system is said to be - statically indeterminate 245.
If the specific enthalpy of wet saturated steam at a pressure of 11 bar is 2681
kJ/kg, find its dryness fraction. At 11 bar, h f= 781 kJ/kg & hfg=2000kJ/kg.==0.95 246.
If the support is a rocker, in drawing tha free-body diagram, the reaction force
has __ unknowns(s) – 1
3
247.
If x = 3t m, where t is in seconds, the particle's velocity when t = 2s is - 36.0 m/s
248.
If Patm = 100 kPa, the pressure at a point where the gage pressure is 300 mmHg is
nearest (γHg = 13.6 γwater) 140 kPa o
249.
If T high =1200 C, find w T(not w net) of the turbine of. 660 kJ/kg
250.
In a heat treating process a 2 kg metal part (speficific heat = 0.5 kJ/kg.K) initially o
o
at 800 C is quenched in a tank containing 200 kg of water initially at 20 C. Calculate the total entropy change of the process immediately after quenching. 1.6 kJ/K (increase) 251.
In a particular power cycle, 350 MJ of heat are transferred into the system each
cycle. The heat transferred out the system is 297.5 MJ per cycle. What is the thermal efficiency of this cycle?==0.15 252.
In a quasiequilbrium process: The pressure is verywhere constant at an instant
253.
In a quasiequilibrium process, the pressure. is everywhere constant at an instant
254.
In figure below, the vertical component of 250N force is - 250N ( /5)
255.
In figure below, what is the particle's position at the end of 4s? – 30m
256.
In projectile motion, acceleration along the y-axis is - uniform
257.
In projectile motion, acceleration along the y-axis is – uniform
258.
In the analysis of the Otto cycle, which do we not assume? The combustions
4
process is a constant-pressure prosess 259.
In the FBD at the pin given, member GC must be in - Compression
260.
In the figure below, is the rod a two-force member? Yes
261.
In the figure below, which equation relates the position of the blocks? XA + 2XB +
XC = L 262.
In the figure below, which equation relates the position of the blocks? XA + 2XB +
XC = L 263.
In the method of joints, typically _______ equations of equilibrium are applied
at every joint. – two 264.
In the pendulum bob, kinetic energy is greatest – at the bottom of its swing
265.
In themodynamics our attention is focused on which form of energy?==internal
energy 266.
Internal forces are not included in an equation of motion analysis because the
internal forces are ______. - equal and opposite and do not affect the calculations. 267.
It is convenient to express the velocity and the acceleration vectors using radial
and transverse components in - polar coordinates
268.
It is proposed that a thermal engine can operate between ocean layers at 10 and o
27 C and produce 10 kW of power while discharging 9900 kJ/min of heat. Such an engine is==impossible 269.
It is the ratio of the ultimate stress to the allowable stress. – 1
270.
It is the ratio of the ultimate stress to the allowable stress. factor of safety
271.
Kinetic energy results from ______. – velocity
272.
Mathane gas is is heated at P = const= 200 kPa from 0 to 300 C. The required
o
heat is==676kj/kg nd
273.
Newton's ____ law forms the basis of the study of dynamics. 2
274.
Nitogen (k = 1.4) is expanded isentropically. Its temperature changes from 620 F
o
o
to 60 F. Find the pressure ratio (P 1/P2). 12.91 o
275.
Nitrogen at 100 C and 600 kPa expands in such a way that it can be
approximated by a polytropic process with n = 1.2. Calculate the heat transfer if the final pressure is 100 kPa.==56.5kj/kg 276.
Oil flows full bore at a velocity of 2 m/s through a nest of 16 tubes in a single
pass cooler. The internal diameter of the tubes is 30 mm and the density of the oil is 0.85 g/li. Find the volume flow in liters per second. 23 li/s 277.
One cubic meter of a perfect gas at a constant pressure of 1 bar and o
3
temperature of 17 C are compressed to avolume of 0.50 m and the final pressure is 6 o
bar. Calculate the final temperature.== 597 C 278.
One kilogram of steam in a cylinder accepts 170 kJ of heat transfer while the o
pressure remains constant at 1000 kPa. Estimate the temperature T 2 if T 1 = 320 C. o
400 C 279.
One kilogram of steam in a cylinder accepts 170 kJ of heat transfer while the o
pressure remains constant at 1000 kPa.Estimate the temperature T 2 if T 1 = 320 C. Estimate the work required for the process of the above problem. 39 kJ 280.
One kilogram of steam in a cylinder requires 320 kJ of heat while P = const = 1 o
Mpa. Find T 2 if T 1 = 300 C. The work required in above problem is nearest. 72 kJ 281.
One kilogram of water ( C v = 4.2 kJ/kg-K ) is heated by 300 BTU of energy. What is
the change in temperature in K? 75.36 K 282.
o
One kilograms of air is compressed atT = const =100 C until the volume is halved.
The rejected heat is. 74 kJ 283.
o
o
One kilograms of air is heated in a rigid container from 20 C to 300 C. The
entropy change is nearest:== 0.48 kJ/K 284.
Power cycles are idealized. Which of the following i s not an idealization?== Heat
transfer does not occur across a finite temperature difference.
285.
o
o
R134a enters an expansion valve as saturated liquid at 16 C and exits at -20 C. Its
quality at the exit is nearest==0.22 286.
R134a is used in an ideal refrigeration cycle between pressure of 120 kPa and
1000 kPa. If the compressor requires 10 hp, c alculate the rate of refrigeration. 21.8 kJ/s 287.
Radiation is emitted by==all materials at a finite temperature
288.
Refrigerant flows through the coil on the back of most refrigerators. This coil is
the: Condenser 289.
o
Saturated water vapor at 400 kPa is heated in a r igid volume until T 2 = 400 C. The
heat transfer is nearest. 406 kJ/kg 290.
Select a correct statement of the first law if kinetic and potential energy changes
are neglected.== Net heat transfer equals the net work for a cycle 291.
Select an acceptable paraphrase of the Kelvin-Planck statement of the second
law.== An engine has to reject heat. 292.
Select an incorrect statement relating to a Carnot cycle. There are two constant-
pressure processes. 293.
Select the correct statement for a liquid. The internal energy depends on
temperature only. 294.
Select the equation which relates the position of the end of the cable B to the
position of block A. - SB + 3SA = L 295.
Select the incorrect statement of the first law (neglect kinetic and potential
energy changes)== The heat transfer equals the internal energy change for an adiabatic process. 296.
Select the Kelvin-Planck statement of the second law. An engine cannot produce
work without discharging heat. 297.
Select the primary reason why an Otto cycle is less efficient than a Carnot cycle.
Heat transfer occurs across a large temperature difference. 298.
Steam at 2.0 kPa is saturated at 17.5oC. In what state will the steam
be at 40o if the pressure is 2.0 kPa?== superheated 299.
o
Steam at 9000 kPa and 600 C passes through a throttling process so that the
pressure is suddenly reduced to 400 kPA. What is the expected temperature after the o
throttle? 570 C 300.
o
Steam enters a valve at 10 MPa and 550 C and exits at 0.8 MPa. What exiting
temperature is expected?==510 C 301.
Steam exists at a pressure of 120 Pa and a temperature of 250K. How many 3
16
molecules are presents in 2 cm at these condintions?== 7 x 10 302.
o
Steam exists in a volume at 288 C and 2 Mpa. Estimate the specific volume. 3
0.1221 m /kg
o
303.
o
Steam initially at 1 Mpa and 200 C expands In a turbine to 40 C and 83% quality.
What I sthe change in entropy? 0.26 kJ/kg.K 304.
Steam is contained in a 4-L volume at a pressure of 1.5 MPa and a temperature o
of 400 C. If the pressure is held constant by expanding the volume while 20 kJ of heat is o
added, the finak temperature is nearest. 825 C o
305.
Steam leaves an industrial boiler at 827.4 kPa and 171.6 C ( hf = 727.25 kJ/kg,
hfg = 2043.2 kJ/kg ). A portion of the steam is passed through a throtting calorimeter and is exhausted to the atmosphere when the calorimeter pressure is 101.4 kPa and a o
temperature of 115.6 C ( h = 2707.6 kJ/kg ) . How much moisture does the steam leaving the boiler contain?==.0308 o
306.
Superheated steam enters an insulated turbine at 4000 kPa and 500 C and
leaves at 20 kPa with x 2= 0.9. If the mass flow rate is 6 kg/s, the power output is nearest -- 6.43 MW 307.
Ten kilograms of 400oC steam are contained in a 734-L tank.
Calculate the error in the pressure if it is calculated using the ideal-gas equation (rather than the more accurate steam tables).==0.06 308.
Ten kilograms of air at 800 kPa is heated at constant pressure from
170oC. the work required is nearest:==660 KJ o
309.
Ten kilograms of an iron at 300 C are chilled in a large volume of ice and water.
Find the total entropy change. 0.88 kJ/K o
310.
Ten kilograms of iron at 300 is chilled in a large volume of ice and water. The
total entropy change is nearest:== 1.60 kJ/ K o
311.
Ten kilograms of saturated liquid water expands until T 2 =200 C while the
pressure remains constant at 500 kPa. Find W 1-2. --2120 kJ 312.
Ten kilograms of saturated steam at 800 kPa are heated at constant pressure to o
400 C. The work required is nearest. 1150 kJ 313.
Tha mass of nitrogen at 150 K and 2 Mpa contained in 0.2 m3 is
nearest:==10.2kg 314.
The air in the cylinder of an air compressed from 100 kPa to 10 MPa. Estimate o
the work required if the air is initially at 100 C. -729 kJ/kg 315.
The ball has a mass of 20 kg and a speed of v = 30 m/s at the instant it is at its
lowest point. Determine the tension in the cord at this instant. 1996N 316.
The beam shown in the figure is 5 inches wide and 10 inches deep. What is the
maximum bending stress? 2888.1 psi 317.
The block (mass = m) is moving upward with a speed v. Draw the FBD if the
kinetic friction coefficient is µk. A PALAGI
318.
The component of the Rankine cycle that leads to a relatively low cycle efficiency
is==the boiler 319.
The distance that the top surface is displaced in the direction of the force divided
by the thickness of the body is known as __________. -- shear strain 320.
The distance that the top surface is displaced in the direction of the force
divided by the thickness of the body is known as __________. Shear strain 321.
The efficiency of an adiabatic steam turbine operating between 10 Mpa,
600oC, and 40 kPa is 80%. What is u2?==2560 kJ/kg 322.
The engines on a commercial jet aircraft operate on which of the basic
cycles?==brayton 323.
The equivalent force and couple moment system acting at A is - (100i)N,
(100k)Nm 324.
The exhaust process in the Otto and diesel cycles is replaced with a constant-
volume process for what primary reason?==to stimulate zero work of the actual exhaust process 325.
The figure as shown is in equilibrium. Determine minimum P to start the blocks
to move. The coefficient of friction between block A and the ground is 0.25 and between block B and the ground is 0.4. 550.02 N 326.
The five forces shown act at point O. What is the magnitude of the resultant
forces? 155.8 N 327.
The flow energy of 124 liters per munite of a fluid passing a boundary to system
is 108.5 kJ/min. Determine the pressure at this point. 875 kPa 328.
The flow energy of 124 liters per munite of a fluid passing a boundary to system
is 108.5 kJ/min. Determine the pressure at this point.==875kPa 329.
The four temperatures in an Otto cycle are T 1 =300 K,T 2 =754 K, T 3 =1600 K,
and T 4 =637 K. If P1=100 kPa, find P2. Assume constant specific heats. The heats added in the Otto cycle of above problem is nearest -- 610 kJ/kg 330.
The frictional effects of the air on the blades of the standing fan creates a couple
moment of MO= 6 N-m on the blades. The value of couple forces at the base of the fan so that the resultant couple moment on the fan is zero is – 20 N 331.
The gage pressure at a depth of 20 m in water is nearest==200kpa
332.
The gage pressure reading on an automobile tire is 240 kPa when the tire
temperature is - 30oC. The automobile is driven to a warmer climate and the tire temperature increases to 65oC. Estimate the gage pressure in tire making reasonable assumptions.==370kPa
333.
The initial temperature and pressure of 8000 cm3 of air are
100oC and 800 kPa, respectively. Determine the necessary heat transfer if the volume does not change and the final pressure is 200 kPa. == -12kJ 334.
The inlet conditions on an air compressor are 50 kPa and 20 oC. To
compress the air to 400 kPa, 5 kW of energy is needed. Neglecting heat transfer and kinetic and potential energy changes, estimate the mass flow rate.== 0.021 kg/s 335.
The magnitude of F for each of the two forces acting on the outer circle, so
that they create the same couple moment as that created by the 100-N forces acting on the inner circle is - 40N 336.
The magnitude of Fr in figure below is – 500N
337.
The magnitude of TAB in the figure to support a 60 kg mass is - 420N
338.
The magnitude of the couple shown is - 1200N-m CW
339.
The magnitude of the x and y - components of the 2-kN force is - Fx = -1.000
kN, Fy = 1.-732 kN 3
340.
The mass of air in a tire with a volume of 0.2 m with a gage pressure of 280 kPa o
at 25 C is nearest. 0.889 kg 341.
The maximum number of unknowns for three-dimensional rigid body is – 6
342.
The maximum number of unknowns for three-dimensional rigid body is – 6
343.
The maximun thermal efficiency posasible for a power cycle operating between
1200oF and 225oF is:== 0.5873 344.
The moment of 100-N force about O is - (141.4k ) Nm
345.
The moment of the couple's two forces about point A is - 200 N-m clockwise
346.
The net entropy change in the universe during any real process is== ≥ 0
347.
The particle shown in the figure travels from A to B in 1s, it then travels from
B to C in 1s. What is the average velocity? 1m/s 348.
The phase change from a liquid to a vapor is referred to as: vaporization
349.
The point that connects the saturated liquid line to the saturated vapor line is
called the:==critical point 350.
The point that connects the saturated-liquid line to the saturated-vapor line is
called the==TRIPLE POINT 351.
The position vector r is represented by - (4j + 3k) m
352.
The pressure of steam at 400 C and u = 2949 kJ/kg is most nearly.17000 kPa
o
353.
The property by virtue of which a body tends to return to its original size or
shape after a deformation and when the deforming forces have been removed. Elasticity 354.
o
the pump work required to compress water at 1.5 Mpa and 50 C to 15 kJ/kg.
What is the efficiency of the pump?==0.91 355.
the Rankine power cycle is idealized. Which of the following is not one of the
idealizations? Heat transfer does not occur across a finite temperature difference. 356.
The resultant of the three forces in figure below is - 638N, 38.9°
357.
The specific gas constant of oxygen is R = 0.25983 kJ/kg.K. If a 2
m3 tank contains 40 kg of oxygen at 40oC, what I sthe gage pressure in the tank?==1.53Mpa 358.
The speed of block A if block B has an upward velocity of 6 ft/s is - 18 ft/s ↓
359.
The standard atmosphere in meters of ammonia (p = 600
kg/m3) is:==17m 360.
The state of an ideal gas is changed in a steady-state open process from 400 kPa 3
3
and 1.2 m to 300 kPa and 1.5m . The relationship between pressure and volume during 1.3
the process is pV = constant. What work is performed==130kJ 361.
The stress in a 90-cm diameter pipe having a wall thickness of 9.5 cm and under
a static head of 70 m of water is - 3.25 Mpa 362.
The system as shown is in equilibrium. Determine the force exerted by cable AB.
89.67 lbs 363.
The system as shown is in equilibrium. Determine the force exerted by cable AB.
89.67 lbs 364.
The temperature of an ideal gas remians constant while the absolute pressure
changes from 103.4 kPaa at 827.2 kPaa. If the initial volume i s 80 loters, what is the final volume? 10 li 365.
The three concurrent forces acting on the body as shown are in equilibrium.
Which of the following most nearly gives the vertical component of the 77.8 kN force? 76.8 kN 366.
The triple scalar product u • ( r x F ) results in - a scalar quantity ( + or - ).
367.
The value of R in the figure below is - 6.00 m
368.
The work done by the spring in the figure is – 25 J
369.
The work needed to isentropically compress 2 kg of air in a cylinder at 400 kPa
and 400oC to 2 Mpa is nearest:== 560kj
o
o
370.
The y-component of the100N force is - 100N cos45 sin 60
371.
The gusset plate G of a bridge joint is subjected to the two member forces o
at A and B. If the force at B is horizontal and the force at A is directed at θ = 30 , determine the magnitude and direction of the resultant force. - R = 252 N, Φ = 97.5 372.
o
This relates displacement, velocity, acceleration and time without reference to
the cause of motion. Kinematics 373.
This relates displacement, velocity, acceleration and time without reference to
the cause of motion. Kinematics 374.
Three cubic meter of air at a pressure of 20 kPag is compressed at constant
temperature as 425 kPa. Calculate the final volume of the air. 0.69m 375.
3
Three temperatures in a diesel cycle are Tinlet
=T1= 300 K, T2 = 950 K, and T3 = 2000 K. Estimate the heat input assuming constant specific heats.==1050kj/kg 376.
Three temperatures in a diesel cycle are Tinlet
=T1= 300 K, T2 = 950 K, and T3 = 2000 K. Estimate the heat input assuming constant specific heats. The temperature T4 for the diesel cycle above problem is nearest==850 377.
Three temperatures in a diesel cycle are T inlet =T 1= 300 K, T 2 = 950 K, and T 3 =
2000 K. Estimate the heat input assuming constant specific heats. The compression ratio for the diesel cycle above problem is nearest.==17.8 378.
Through an isentropic process, a piston compresses 2 kg of an ideal gas at 150 o
kPa and 35 C in a cylinder to a pressure of 300 kPa. The specific heat of the gas for constant pressure processes is 5 kJ/kg.K; for constant volume processes, the specific o
heat is 3 kJ/kg.K. What is the final temperature o fthe gas? 134 C 379.
To determine Fr in the figure, we use - Sine Law
380.
Two Carnot engines operate in series such that the heat rejected from one is the
heat input to the other. The heat transfer from the high -temperature reservoir is 500 kJ. If the overall temperature limits are 1000K and 400K and both engines produce equal work, determine the intermediate temperature between the two engines.==700K 381.
Two force of 20 units and 30 units act at right angles. What is the magnitude of
the resultantforce? 36 382.
Two force of 20 units and 30 units act at right angles. What is the magnitude of
the resultantforce? 36
383.
Two hundred kilowatts are to be produced by steam turbine. The outlet steam is
to be saturated at 80 kPa and the steam entering will be at 600oC. For an isentropic process, determine the mass flow rate of steam.==0.198kg/s 384.
Two hundred kilowatts are to be produced by steam turbine. The outlet steam is o
to be saturated at 80 kPa and the steam entering will be at 600 C. For an isentropic process, determine the mass flow rate of steam.== 0.198 kg/s o
385.
Two kilograms of air are compressed from 120 kPa and 27 C to 600 kPa in a rigid
container. Calculate the entropy change.==2.31kj/kg 386.
Two kilograms of air are compressed from 210 to 2000 kPa while maintaining the o
temperature constant at 30 C. The required heat transfer is nearest. -392 kJ 3
387.
Two kilograms of air are stored in a rigid volume of 2 m with the temperature o
initially at 300 C. Heat is transferred from the air until the pressure reaches 120 kPa. Calculate the entropy change of the air. Calculate the entropy change of the universe for the above problem if the surroundings o
are at 27 C. -- 0.289 kJ/K 388.
Two kilograms of saturated steam at 100oC are contained in a
cylinder. If the steam undergoes an isentropic expansion to 20 kPa, determine the work output.== 447 kJ 389.
Two men are just able to lift a 300 kg weight with a crowbar when the fulcrum
for the lever is 0.3 m from the weight. The first man exerts his strength at 0.9 m while the second is at 1.5 m from the fulcrum respectively. If the men interchanged positions, they can ralse a 340 kg weight. What force does the first man exert? 50kg 390.
Two points in 3 - D space have coordinates of P(1, 2, 3) and Q(4, 5, 6) meters.
The position vectorr QP is given by - { -3 i - 3 j - 3 k } m o
391.
Water are 25 C has a vapor pressure of 3.1504 kPa. Compound B (MW = 52.135) o
at 25 C has a vapor pressure of 7.2601 kPa. If 75 g of liquid water are mixed with 45 g of liquid compound B, what is the resulting vapor pressure of the solution?==3.9kPa 392.
Water enters the condenser at 30oC and leaves at
60oC. What is the temperature difference in oF?==54 393.
What are the processes in an ideal Otto combustion cycle?== two constant
volume processes and two isentropic processes 394.
What cycle or process does the temperature-entropy diagram represent?
Rankine cycle with superhaeted steam 395.
What does the term "tonnage" refer to in regard to refrigeration cycles? the rate
at which heat is removed from a refrigeration cycle. 396.
What is the approximate change in entropy from state A to state B?==4.6kj/kg
397.
What is the approximate change in entropy from state B to state C? 0 kJ/kg⋅ K
398.
What is the change in internal energy of air (assumed to be an ideal gas) colled o
o
from 550 C to 100 C? 320 kJ/kg 399.
What is the circumferential stress in the walls (in the figure shown) if the inside
diameter is 10 in. and the wall thickness is 1 in. 6365 psi 400.
What is the final mass of Freon-12 vapor?==10kg
401.
What is the final volume of Freon-12 liquid?==0.31m
402.
What is the mass of steam contained behind the piston?==0.76kg
403.
What is the maximum stress of the structure shown –1400 psi
404.
What is the maximum thermal efficiency possible for a power cycle operating
3
o
o
between 600 C and 110 C. 0.56 405.
What is the quality of the steam after it has expanced in the turbines? 0.92
406.
What is the stress in an 8-inch round x 16-inch high concrete cylinder (E = 2.5 x
106 psi) when the unit deformation is 0.0012 inch/inch? – 3000psi 407.
What Is the temperature in oC of 2 liters of water at
30oC after 500 Calories of heat have been added?==30.2 408.
What is the total required heating energy in raising the temperature of a given
amount of water when the energy supplied is 1000 kwh with heat losses of 25%? 1333 409.
What is the total steam flow rate through all the turbines==270kg/s
410.
What is the volume at state A? 0.10 m
411.
What is the work done during the expansion process? 105 kJ
412.
What net work is derived from one complete A-B-C cycle? -2.3kj
413.
What power in kilowatts a 10-mm diameter solid shaft at 30 rps can transmit if
3
the allowable torsional shreading stress is 40 MPa? 1.48 kW 414.
What pressure force exists on an 80 cm-diameter-horizontal area at a depth
below the surface of a lake? 1480 kN 415.
What pressure is column of water 100 cm high equivalent to?==9807N/M2
416.
What was the mass of Freon-12 added to the tank?== 72 kg
417.
What weight in pounds can be lifted by a screw that has an efficiency or 80% if it
is operated by a 50 lb force at the end of a 30 inched lever and the pitch of the screw is 1/2 inch? - 15, 000 418.
When t = 0, s = 0.5, v = 1m/s. If v = (3t + 1) m/s, where t is in seconds, compute
the distance s travelled by the particle when t = 1s. – 3m
419.
When t = 0, s = 0.5, v = 1m/s. If v = (3t + 1) m/s, where t is in seconds, compute
the distance s traveled by the particle when t = 1s. – 3m 420.
When the volume of an ideal gas is doubled while the temperature is halved,
what happens to the pressure? Pressure is quartered 421.
Which cycle do most steam turbine power-generating plants operate
on?==RANKINE 422.
Which cycle do most steam turbine power-generating plants operate
on?==RANKINE 423.
Which equation of equilibrium allows you to determine F B right away? - MA = 0
424.
Which equation of equilibrium allows you to determine F B right away? Σ MA = 0
425.
Which of the following can be assumed to be reversible? A piston compressing
gas in a race engine 426.
Which of the following does not transfer work to or from a system? A membrane
that bursts 427.
Which of the following first-law statements is wrong?<== The heat transfer
equals the enthalpy change for an adiabatic process. 428.
Which of the following is a proper statement of the second law of
thermodynamics?== It is impossible for a system working in a complete cycle to accomplish, as its sole effect, the transfer of heat from a body at a given temperature to a body at a higher temperature. 429.
Which of the following is a quasiequilibrium process? Compression of the air-fuel
mixture in a cylinder 430.
Which of the following is a quasiequilibrium process?== Compression of air in a
cylinder 431.
Which of the following is not a control volume? Insulated tank
432.
Which of the following is not a curvilinear motion? - a rotating disc
433.
Which of the following is not an acceptable SI unit?== Density measured in
grams per cubic centimeter 434.
Which of the following is not an extensive property? Density
435.
Which of the following is not an extensive property? Temperature
436.
Which of the following is not an extensive property?==density
437.
Which of the following principles is the closest interpretation of the first law of
thermodynamics for a closed system? The net energy crossing the sytem boundary I sthe change in energy inside the system 438.
Which of the following processes can be approximated by a quasiequilibrium
process?== The xepansion of combustion gases in the cylinder of an automobile engine
