All Matches

Solution Library

Expert Answer

Textbooks

Search Textbook questions, tutors and Books

Oops, something went wrong!

Change your search query and then try again

Result Not Found

Books FREE
Tutors
Study Help
Hire a Tutor
AI Study Help New

Search
Sign In
Register

study help
engineering
mechanical engineering

Questions and Answers of Mechanical Engineering

1-kg of water that is initially at 90oC with a quality of 10 percent occupies a spring-loaded piston - cylinder device, such as that in Fig. P4 - 21. This device is now heated until the pressure
0.75-kg water that is initially at 0.5 MPa and 30 percent quality occupies a spring-loaded piston-cylinder device. This device is now cooled until the water is a saturated liquid at 100oC. Calculate
An ideal gas undergoes two processes in a pistoncylinder device as follows: 1-2 Polytropic compression from T1 and P1 with a polytropic exponent n and a compression ratio of r = V1/V2. (a) Sketch
A piston-cylinder device contains 50 kg of water at 250 kPa and 25oC. The cross-sectional area of the piston is 0.1 m2. Heat is now transferred to the water, causing part of it to evaporate and
Reconsider Prob. 4-24. Using the EES software, investigate the effect of the spring constant on the final pressure in the cylinder and the boundary work done. Let the spring constant vary from 50
Complete the table below on the basis of the conservation of energy principle for a closedsystem.
A closed system undergoes a process in which there is no internal energy change. During this process, the system produces 1.1 × 106 1bf·ft of work. Calculate the heat transfer for this process, in
A rigid container equipped with a stirring device contains 2.5 kg of motor oil. Determine the rate of specific energy increase when heat is transferred to the oil at a rate of 1 W, and 1.5 W of power
A 0.5-m3 rigid tank contains refrigerant-134a initially at 160 kPa and 40 percent quality. Heat is now transferred to the refrigerant until the pressure reaches 700 kPa. Determine (a) The mass of the
The volume of 1 kg of helium in a piston-cylinder device is initially 5 m3. Now helium is compressed to 2 m3 while its pressure is maintained constant at 180 kPa. Determine the initial and final
A 20-ft3 rigid tank initially contains saturated refrigerant- 134a vapor at 160 psia. As a result of heat transfer from the refrigerant, the pressure drops to 50 psia. Show the process on a P-v
A rigid 10-L vessel initially contains a mixture of liquid water and vapor at 100oC with 12.3 percent quality. The mixture is then heated until its temperature is 150oC. Calculate the heat transfer
A fixed mass of saturated water vapor at 400 kPa is isothermally cooled until it is a saturated liquid. Calculate the amount of heat rejected during this process, in kJ/kg.
A piston - cylinder device contains steam initially at 1 MPa, 450oC, and 2.5 m3. Steam is allowed to cool at constant pressure until it first starts condensing. Show the process on a T v diagram with
An insulated piston-cylinder device contains 5 L of saturated liquid water at a constant pressure of 175 kPa. Water is stirred by a paddle wheel while a current of 8 A flows for 45 min through a
A piston - cylinder device initially contains steam at 200 kPa, 200oC, and 0.4 m3. At this state, a linear spring (F ˆž x) is touching the piston but exerts no force on it. Heat is now slowly
Reconsider Prob. 4 - 35. Using EES (or other) software, investigate the effect of the initial temperature of steam on the final temperature, the work done, and the total heat transfer. Let the
A piston - cylinder device initially contains 0.8 m3 of saturated water vapor at 250 kPa. At this state, the piston is resting on a set of stops, and the mass of the piston is such that a pressure of
A 40-L electrical radiator containing heating oil is placed in a 50-m3 room. Both the room and the oil in the radiator are initially at 10oC. The radiator with a rating of 2.4 kW is now turned on. At
Steam at 75 kPa and 8 percent quality is contained in a spring-loaded piston - cylinder device, as shown in Fig. P4 - 39, with an initial volume of 2 m3. Steam is now heated until its volume is 5 m3
Calculate the total work, in Btu, for process 1 - 3 shown in Fig. P4 - 4E.
Saturated R-134a vapor at 100oF is condensed at constant pressure to a saturated liquid in a closed piston - cylinder system. Calculate the heat transfer and work done during this process, in Btu/lbm.
An insulated tank is divided into two parts by a partition. One part of the tank contains 2.5 kg of compressed liquid water at 60oC and 600 kPa while the other part is evacuated. The partition is now
Reconsider Prob. 4 - 41. Using EES (or other) software, investigate the effect of the initial pressure of water on the final temperature in the tank. Let the initial pressure vary from 100 to 600
Show that for an ideal gas c-p = c-v + Ru
A piston - cylinder device initially contains 0.07 m3 of nitrogen gas at 130 kPa and 120oC. The nitrogen is now expanded polytropically to a state of 100 kPa and 100oC. Determine the boundary work
What is the change in the enthalpy, in kJ/kg, of oxygen as its temperature changes from 150 to 250oC? Is there any difference if the temperature change were from 0 to 100oC? Does the pressure at the
Air is compressed from 20 psia and 70oF to 150 psia in a compressor. The compressor is operated such that the air temperature remains constant. Calculate the change in the specific volume of air as
The temperature of 2 kg of neon is increased from 20 to 180oC. Calculate the change in the total internal energy of the neon, in kJ. Would the internal energy change be any different if the neon
Calculate the change in the enthalpy of argon, in kJ/kg, when it is cooled from 75 to 25oC. If neon had undergone this same change of temperature, would its enthalpy change have been any different?
Determine the internal energy change Du of hydrogen, in kJ/kg, as it is heated from 200 to 800 K, using (a) The empirical specific heat equation as a function of temperature (Table A - 2c), (b) The
Determine the enthalpy change Dh of nitrogen, in kJ/kg, as it is heated from 600 to 1000 K, using (a) The empirical specific heat equation as a function of temperature (Table A - 2c),(b) The cp value
1-ft3 of air is contained in the spring-loaded pistoncylinder device shown in Fig. P4-56E. The spring constant is 5 lbf/in, and the piston diameter is 10 in. When no force is exerted by the spring on
Is it possible to compress an ideal gas isothermally in an adiabatic piston-cylinder device? Explain.
A 3-m3 rigid tank contains hydrogen at 250 kPa and 550 K. The gas is now cooled until its temperature drops to 350 K. Determine (a) The final pressure in the tank and (b) The amount of heat transfer.
A 10-ft3 tank contains oxygen initially at 14.7 psia and 808F. A paddle wheel within the tank is rotated until the pressure inside rises to 20 psia. During the process 20 Btu of heat is lost to the
A piston-cylinder device with a set of stops initially contains 0.6 kg of steam at 1.0 MPa and 4008C. The location of the stops corresponds to 40 percent of the initial volume. Now the steam is
A rigid tank contains 10 lbm of air at 30 psia and 65oF. The air is now heated until its pressure doubles. Determine (a) The volume of the tank and (b) The amount of heat transfer.
Nitrogen gas to 20 psia and 100oF initially occupies a volume of 1 ft3 in a rigid container equipped with a stirring paddle wheel. After 5000 lbf·ft of paddle wheel work is done on nitrogen, what is
An insulated rigid tank is divided into two equal parts by a partition. Initially, one part contains 4 kg of an ideal gas at 800 kPa and 50oC, and the other part is evacuated. The partition is now
A 4-m × 5 - m × 6-m room is to be heated by a baseboard resistance heater. It is desired that the resistance heater be able to raise the air temperature in the room from 5 to 25oC within 11 min.
A student living in a 3-m 3 4-m 3 4-m dormitory room turns on her 100-W fan before she leaves the room on a summer day, hoping that the room will be cooler when she comes back in the evening.
A 4-m Ã— 5-m Ã— 7-m room is heated by the radiator of a steam-heating system. The steam radiator transfers heat at a rate of 10,000 kJ/h, and a 100-W fan is used to distribute the warm air in
Argon is compressed in a polytropic process with n 5 1.2 from 120 kPa and 10oC to 800 kPa in a piston - cylinder device. Determine the work produced and heat transferred during this compression
An insulated piston - cylinder device contains 100 L of air at 400 kPa and 25oC. A paddle wheel within the cylinder is rotated until 15 kJ of work is done on the air while the pressure is held
A spring - loaded piston-cylinder device contains 1 kg of carbon dioxide. This system is heated from 100 kPa and 25oC to 1000 kPa and 300oC. Determine the total heat transfer to and work produced by
A piston - cylinder device contains 25 ft3 of nitrogen at 40 psia and 700oF. Nitrogen is now allowed to cool at constant pressure until the temperature drops to 200oF. Using specific heats at the
A piston - cylinder device initially contains 0.07 m3 of nitrogen gas at 130 kPa and 180oC. The nitrogen is now expanded to a pressure of 80 kPa polytropically with a polytropic exponent whose value
Air is contained in a variable-load piston-cylinder device equipped with a paddle wheel. Initially, air is at 400 kPa and 17oC. The paddle wheel is now turned by an external electric motor until 75
A mass of 15 kg of air in a piston - cylinder device is heated from 25 to 77oC by passing current through a resistance heater inside the cylinder. The pressure inside the cylinder is held constant at
A piston-cylinder device contains 2.2 kg of nitrogen initially at 100 kPa and 25oC. The nitrogen is now compressed slowly in a polytropic process during which PV 1.3 5 constant until the volume is
Reconsider Prob. 4-72. Using EES (or other) software, plot the process described in the problem on a P-V diagram, and investigate the effect of the polytropic exponent n on the boundary work and heat
A piston - cylinder device contains 3 ft3 of air at 60 psia and 150oF. Heat is transferred to the air in the amount of 40 Btu as the air expands isothermally. Determine the amount of boundary work
A piston - cylinder device, with a set of stops on the top, initially contains 3 kg of air at 200 kPa and 27oC. Heat is now transferred to the air, and the piston rises until it hits the stops, at
Air is contained in a cylinder device fitted with a piston-cylinder. The piston initially rests on a set of stops, and a pressure of 200 kPa is required to move the piston. Initially, the air is at
Air is contained in a piston - cylinder device at 600 kPa and oC, and occupies a volume of 0.8 m3. The air undergoes and isothermal (constant temperature) process until the pressure in reduced to 300
A piston - cylinder device contains 4 kg of argon at 250 kPa and 35oC. During a quasi equilibrium, isothermal expansion process, 15 kJ of boundary work is done by the system, and 3 kJ of paddle-wheel
The state of liquid water is changed from 50 psia and 50oF to 2000 psia and 100oF. Determine the change in the internal energy and enthalpy of water on the basis of the (a) Compressed liquid tables,
A mass of 5 kg of saturated water vapor at 300 kPa is heated at constant pressure until the temperature reaches 200oC. Calculate the work done by the steam during this process.
During a picnic on a hot summer day, all the cold drinks disappeared quickly, and the only available drinks were those at the ambient temperature of 858F. In an effort to cool a 12-fluid-oz drink in
Consider a 1000-W iron whose base plate is made of 0.5-cm-thick aluminum alloy 2024-T6 (Æ¿ = 2770 kg/m3 and cp = 875 J/kg·oC). The base plate has a surface area of 0.03 m2.
Stainless steel ball bearings (ƿ = 8085 kg/m3 and cp = 0.480 kJ/kg·oC) having a diameter of 1.2 cm are to be quenched in water at a rate of 800 per minute. The balls leave the oven at a uniform
ln a production facility, 1.6-in-thick 2-ft Ã— 2-ft square brass plates (Æ¿ = 532.5 lbm/ft3 and cp = 0.091 Btu/lbm·8F) that are initially at a uniform temperature of
Long cylindrical steel rods (ƿ = 7833 kg/m3 and cp = 0.465 kJ/kg·oC) of 8-cm diameter are heat-treated by drawing them at a velocity of 2 m/min through an oven maintained at 900oC. If the rods
An electronic device dissipating 25 W has a mass of 20 g and a specific heat of 850 J/kg·oC. The device is lightly used, and it is on for 5 min and then off for several hours, during which it cools
Reconsider Prob. 4-85. Using EES (or other) software, investigate the effect of the mass of the heat sink on the maximum device temperature. Let the mass of heat sink vary from 0 to 1 kg. Plot the
If you ever slapped someone or got slapped yourself, you probably remember the burning sensation. Imagine you had the unfortunate occasion of being slapped by an angry person, which caused the
In a manufacturing facility, 5-cm-diameter brass balls (Æ¿ = 8522 kg/m3 and cp = 0.385 kJ/kg · oC) initially at 120oC are quenched in a water bath at 50oC for a period of 2 min at
Repeat Prob. 4-88 for aluminum balls.
1-m3 of saturated liquid water at 200oC is expanded isothermally in a closed system until its quality is 80 percent. Determine the total work produced by this expansion, in kJ.
Is the metabolizable energy content of a food the same as the energy released when it is burned in a bomb calorimeter? If not, how does it differ?
Is the number of prospective occupants an important consideration in the design of heating and cooling systems of classrooms? Explain.
What do you think of a diet program that allows for generous amounts of bread and rice provided that no butter or margarine is added?
The average specific heat of the human body is 3.6 kJ/kg · oC. If the body temperature of an 80-kg man rises from 37oC to 39oC during strenuous exercise, determine the increase in the thermal energy
Consider two identical 80-kg men who are eating identical meals and doing identical things except that one of them jogs for 30 min every day while the other watches TV. Determine the weight
A 68-kg woman is planning to bicycle for an hour. If she is to meet her entire energy needs while bicycling by eating 30-g chocolate candy bars, determine how many candy bars she needs to take with
A 90-kg man gives in to temptation and eats an entire 1-L box of ice cream. How long does this man need to jog to burn off the calories he consumed from the ice cream?
A 60-kg man used to have an apple every day after dinner without losing or gaining any weight. He now eats a 200-ml serving of ice cream instead of an apple and walks 20 min every day. On this new
Consider a man who has 20 kg of body fat when he goes on a hunger strike. Determine how long he can survive on his body fat alone.
Consider two identical 50-kg women, Candy and Wendy, who are doing identical things and eating identical food except that Candy eats her baked potato with four teaspoons of butter while Wendy eats
A cyclone separator like that in Fig. P5 - 10 is used to remove fine solid particles, such as fly ash, that are suspended in a gas stream. In the flue-gas system of an electrical power plant, the
A long roll of 2-m-wide and 0.5-cm-thick 1-Mn manganese steel plate (Æ¿ = 7854 kg/m3 and cp = 0.434 kJ/kg·°C) coming off a furnace at 820°C is to be quenched in an oil
Reconsider Prob. 5-100. Using EES (or other) software, investigate the effect of the moving velocity of the steel plate on the rate of heat transfer from the oil bath. Let the velocity vary from 5 to
The hot-water needs of a household are to be met by heating water at 55°F to 180°F by a parabolic solar collector at a rate of 4 lbm/s. Water flows through a 1.25-indiameter thin aluminum tube
A house has an electric heating system that consists of a 300 - W fan and an electric resistance heating element placed in a duct. Air flows steadily through the duct at a rate of 0.6 kg/s and
Steam enters a long, horizontal pipe with an inlet diameter of D1 = 16 cm at 2 MPa and 300°C with a velocity of 2.5 m/s. Farther downstream, the conditions are 1.8 MPa and 250°C, and the diameter
Refrigerant-134a enters the condenser of a refrigerator at 900 kPa and 608C, and leaves as a saturated liquid at the same pressure. Determine the heat transfer from the refrigerant per unit mass.
Saturated liquid water is heated at constant pressure in a steady-flow device until it is a saturated vapor. Calculate the heat transfer, in kJ/kg, when the vaporization is done at a pressure of 500
Water is heated in an insulated, constant-diameter tube by a 7-kW electric resistance heater. If the water enters the heater steadily at 20°C and leaves at 75°C, determine the mass flow rate of
Air at 300 K and 100 kPa steadily flows into a hair dryer having electrical work input of 1500 W. Because of the size of the air intake, the inlet velocity of the air is negligible. The air
Reconsider Prob. 5-108. Using EES (or other) software, investigate the effect of the exit velocity on the mass flow rate and the exit volume flow rate. Let the exit velocity vary from 5 to 25 m/s.
A spherical hot-air balloon is initially filled with air at 120 kPa and 20°C with an initial diameter of 5 m. Air enters this balloon at 120 kPa and 20°C with a velocity of 3 m/s through a
Air enters the duct of an air-conditioning system at 15 psia and 50°F at a volume flow rate of 450 ft3/min. The diameter of the duct is 10 in, and heat is transferred to the air in the duct from the
A rigid, insulated tank that is initially evacuated is connected through a valve to a supply line that carries steam at 4 MPa. Now the valve is opened, and steam is allowed to flow into the tank
A 2-m3 rigid insulated tank initially containing saturated water vapor at 1 MPa is connected through a valve to a supply line that carries steam at 400oC. Now the valve is opened, and steam is
A rigid, insulated tank that is initially evacuated is connected through a valve to a supply line that carries helium at 200 kPa and 120oC. Now the valve is opened, and helium is allowed to flow into
Consider a 35-L evacuated rigid bottle that is surrounded by the atmosphere at 100 kPa and 22°C. A valve at the neck of the bottle is now opened and the atmospheric air is allowed to flow into the
A 0.2-m3 rigid tank equipped with a pressure regulator contains steam at 2 MPa and 300°C. The steam in the tank is now heated. The regulator keeps the steam pressure constant by letting out some
3-ft3 rigid tank initially contains saturated water vapor at 300°F. The tank is connected by a valve to a supply line that carries steam at 200 psia and 400°F. Now the valve is opened, and steam is
A 4-L pressure cooker has an operating pressure of 175 kPa. Initially, one-half of the volume is filled with liquid and the other half with vapor. If it is desired that the pressure cooker not run

Showing 13700 - 13800 of 18208

First
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
Last

Services

Sitemap
Fun
Definitions
Become Tutor
Study Help Categories
Recent Questions
Expert Questions

Company Info

Security
Copyrights
Privacy Policy
Terms & Conditions
SolutionInn Fee
Scholarship

Get In Touch

About Us
Contact Us
Career
Jobs
FAQ
Campus Ambassador

Secure Payment

Download Our App

© 2024 SolutionInn. All Rights Reserved