EBK THERMODYNAMICS: AN ENGINEERING APPR
8th Edition
ISBN: 9780100257054
Author: CENGEL
Publisher: YUZU
expand_more
expand_more
format_list_bulleted
Textbook Question
Chapter 14.7, Problem 20P
Andy and Wendy both wear glasses. On a cold winter day, Andy comes from the cold outside and enters the warm house, while Wendy leaves the house and goes outside. Whose glasses are more likely to be fogged? Explain.
Expert Solution & Answer

Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
HW8
A shaft fitted with a flywheel rotates at 650 r.p.m. and drives a machine. The
torque of machine varies in a cyclic manner over a period of 2 revolutions. The
torque rises from 650 N-m to 2200 N-m uniformly during 110° and remains
constant for the following 270°. It then falls uniformly to 600 N-m during the next
100° and remains constant for the end cycle, the cycle being repeated thereafter.
Determine the power required to drive the machine and percentage fluctuation in
speed, if the driving torque applied to the shaft is constant and the mass of the
flywheel is 180 kg with radius of gyration of 35 cm.
HW9
units of h. show all work
4. Steam flows steadily through a turbine at a rate of 47,000 lbm/h, entering at 1000 psia
and 800°F and leaving at 6 psia as saturated vapor. If the power generated by the
turbine is 3.7 MW, determine the rate of heat loss from the steam.
Chapter 14 Solutions
EBK THERMODYNAMICS: AN ENGINEERING APPR
Ch. 14.7 - What is the difference between dry air and...Ch. 14.7 - What is the difference between the specific...Ch. 14.7 - Can the water vapor in air be treated as an ideal...Ch. 14.7 - Is the relative humidity of saturated air...Ch. 14.7 - Is it possible to obtain saturated air from...Ch. 14.7 - Moist air is passed through a cooling section...Ch. 14.7 - How will (a) the specific humidity and (b) the...Ch. 14.7 - Prob. 8PCh. 14.7 - Consider a tank that contains moist air at 3 atm...Ch. 14.7 - Why are the chilled water lines always wrapped...
Ch. 14.7 - A tank contains 15 kg of dry air and 0.17 kg of...Ch. 14.7 - Prob. 12PCh. 14.7 - Prob. 13PCh. 14.7 - 14–13 A room contains air at 20°C and 98 kPa at a...Ch. 14.7 - A room contains air at 85F and 13.5 psia at a...Ch. 14.7 - An 8-m3 tank contains saturated air at 30C, 105...Ch. 14.7 - Prob. 17PCh. 14.7 - Prob. 18PCh. 14.7 - Prob. 19PCh. 14.7 - Andy and Wendy both wear glasses. On a cold winter...Ch. 14.7 - In summer, the outer surface of a glass filled...Ch. 14.7 - In some climates, cleaning the ice off the...Ch. 14.7 - Prob. 23PCh. 14.7 - Prob. 24PCh. 14.7 - Prob. 25PCh. 14.7 - Prob. 26PCh. 14.7 - A thirsty woman opens the refrigerator and picks...Ch. 14.7 - Prob. 28PCh. 14.7 - The air in a room has a dry-bulb temperature of...Ch. 14.7 - Prob. 31PCh. 14.7 - Prob. 32PCh. 14.7 - How do constant-enthalpy and...Ch. 14.7 - At what states on the psychrometric chart are the...Ch. 14.7 - How is the dew-point temperature at a specified...Ch. 14.7 - Can the enthalpy values determined from a...Ch. 14.7 - Prob. 37PCh. 14.7 - Prob. 39PCh. 14.7 - Prob. 41PCh. 14.7 - Prob. 42PCh. 14.7 - Prob. 43PCh. 14.7 - Prob. 44PCh. 14.7 - What does a modern air-conditioning system do...Ch. 14.7 - How does the human body respond to (a) hot...Ch. 14.7 - Prob. 47PCh. 14.7 - How does the air motion in the vicinity of the...Ch. 14.7 - Consider a tennis match in cold weather where both...Ch. 14.7 - Prob. 50PCh. 14.7 - Prob. 51PCh. 14.7 - Prob. 52PCh. 14.7 - What is metabolism? What is the range of metabolic...Ch. 14.7 - What is sensible heat? How is the sensible heat...Ch. 14.7 - Prob. 55PCh. 14.7 - Prob. 56PCh. 14.7 - Prob. 57PCh. 14.7 - Prob. 58PCh. 14.7 - Repeat Prob. 1459 for an infiltration rate of 1.8...Ch. 14.7 - An average person produces 0.25 kg of moisture...Ch. 14.7 - An average (1.82 kg or 4.0 lbm) chicken has a...Ch. 14.7 - How do relative and specific humidities change...Ch. 14.7 - Prob. 63PCh. 14.7 - Prob. 64PCh. 14.7 - Prob. 65PCh. 14.7 - Humid air at 40 psia, 50F, and 90 percent relative...Ch. 14.7 - Air enters a 30-cm-diameter cooling section at 1...Ch. 14.7 - Prob. 68PCh. 14.7 - Prob. 69PCh. 14.7 - Why is heated air sometimes humidified?Ch. 14.7 - Air at 1 atm, 15C, and 60 percent relative...Ch. 14.7 - Prob. 72PCh. 14.7 - An air-conditioning system operates at a total...Ch. 14.7 - Prob. 74PCh. 14.7 - Why is cooled air sometimes reheated in summer...Ch. 14.7 - Prob. 76PCh. 14.7 - Prob. 77PCh. 14.7 - Air enters a 40-cm-diameter cooling section at 1...Ch. 14.7 - Repeat Prob. 1479 for a total pressure of 88 kPa...Ch. 14.7 - Prob. 81PCh. 14.7 - Prob. 83PCh. 14.7 - Prob. 84PCh. 14.7 - Prob. 85PCh. 14.7 - Atmospheric air at 1 atm, 32C, and 95 percent...Ch. 14.7 - Prob. 88PCh. 14.7 - Prob. 89PCh. 14.7 - Does an evaporation process have to involve heat...Ch. 14.7 - Prob. 93PCh. 14.7 - Prob. 94PCh. 14.7 - Air at 1 atm, 20C, and 70 percent relative...Ch. 14.7 - Two unsaturated airstreams are mixed...Ch. 14.7 - Consider the adiabatic mixing of two airstreams....Ch. 14.7 - Prob. 98PCh. 14.7 - Two airstreams are mixed steadily and...Ch. 14.7 - A stream of warm air with a dry-bulb temperature...Ch. 14.7 - Prob. 104PCh. 14.7 - How does a natural-draft wet cooling tower work?Ch. 14.7 - What is a spray pond? How does its performance...Ch. 14.7 - The cooling water from the condenser of a power...Ch. 14.7 - Prob. 108PCh. 14.7 - A wet cooling tower is to cool 60 kg/s of water...Ch. 14.7 - Prob. 110PCh. 14.7 - Prob. 111PCh. 14.7 - Prob. 112PCh. 14.7 - Prob. 113RPCh. 14.7 - Prob. 114RPCh. 14.7 - Prob. 115RPCh. 14.7 - Prob. 116RPCh. 14.7 - Prob. 117RPCh. 14.7 - Prob. 118RPCh. 14.7 - Prob. 119RPCh. 14.7 - Prob. 120RPCh. 14.7 - 14–121 The relative humidity inside dacha of Prob....Ch. 14.7 - Prob. 122RPCh. 14.7 - Prob. 124RPCh. 14.7 - 14–126E Air at 15 psia, 60°F, and 70 percent...Ch. 14.7 - Prob. 127RPCh. 14.7 - Air enters a cooling section at 97 kPa, 35C, and...Ch. 14.7 - Prob. 129RPCh. 14.7 - Humid air at 101.3 kPa, 36C dry bulb and 65...Ch. 14.7 - 14–131 Air enters an air-conditioning system that...Ch. 14.7 - Prob. 132RPCh. 14.7 - Prob. 133RPCh. 14.7 - Conditioned air at 13C and 90 percent relative...Ch. 14.7 - Prob. 138RPCh. 14.7 - A room is filled with saturated moist air at 25C...Ch. 14.7 - Prob. 141FEPCh. 14.7 - A 40-m3 room contains air at 30C and a total...Ch. 14.7 - Prob. 143FEPCh. 14.7 - The air in a house is at 25C and 65 percent...Ch. 14.7 - On the psychrometric chart, a cooling and...Ch. 14.7 - On the psychrometric chart, a heating and...Ch. 14.7 - An airstream at a specified temperature and...Ch. 14.7 - Prob. 148FEPCh. 14.7 - Air at a total pressure of 90 kPa, 15C, and 75...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.Similar questions
- 3. Water enters the constant 125-mm inside-diameter tubes of a boiler at 7.5 MPa and 60°C and leaves the tubes at 6 MPa and 500°C with a velocity of 75 m/s. Calculate the velocity of the water at the tube inlet and the inlet volume flow rate.arrow_forward2. A piston-cylinder device contains 2.4 kg of nitrogen initially at 120 kPa and 27°C. The nitrogen is now compressed slowly in a polytropic process during which PV1.3 = constant until the volume is reduced by one-half. Determine the work done and the heat transfer for this process.arrow_forward1. 1.25 m³ of saturated liquid water at 225°C is expanded isothermally in a closed system until its quality is 75 percent. Determine the total work produced by this expansion, in kJ.arrow_forward
- An undamped single-degree-of-freedom system is subjected to dynamic excitation as shown in Figure 1.• System properties: m = 1, c = 0, k = (6π)2.• Force excitation: p(t) = posin(ωt) where po = 9 and ω = 2π.• Initial conditions: u(t = 0) = 0 and ̇u(t = 0) = 0.Please, complete Parts (a) through (d) using any computational tool of your preference. The preferred toolis MATLAB. Print and turn in a single pdf file that will include your code/calculations and your plots.(a) Generate the solution using a linear interpolation of the load over each time step (note that hereyou can use the undamped coefficients). Plot the displacement response for the first 4 seconds andcompare to the exact closed form solution. Repeat using the following time step sizes, ∆t = 0.01,0.05, 0.15, 0.20 seconds. Include the closed form solution and the solutions for different ∆t values in asingle plot. Please, provide your observations by comparing the closed form solution with the solutionsderived using the four…arrow_forwardAssume multiple single degree of freedom systems with natural periods T ∈ [0.05, 2.00] seconds with in-crement of period dT = 0.05 seconds. Assume three cases of damping ratio: Case (A) ξ = 0%; Case (B)ξ = 2%; Case (C) ξ = 5%. The systems are initially at rest. Thus, the initial conditions are u(t = 0) = 0 anḋu(t = 0) = 0. The systems are subjected to the base acceleration that was provided in the ElCentro.txt file(i.e., first column). For the systems in Case (A), Case (B), and Case (C) and for each natural period computethe peak acceleration, peak velocity, and peak displacement responses to the given base excitation. Please,use the Newmark method for β = 1/4 (average acceleration) to compute the responses. Create threeplots with three lines in each plot. The first plot will have the peak accelerations in y-axis and the naturalperiod of the system in x-axis. The second plot will have the peak velocities in y-axis and the natural periodof the system in x-axis. The third plot will have…arrow_forwardBoth portions of the rod ABC are made of an aluminum for which E = 70 GPa. Based on the given information find: 1- deformation at A 2- stress in BC 3- Total strain 4- If v (Poisson ratio is 0.25, find the lateral deformation of AB Last 3 student ID+ 300 mm=L2 724 A P=Last 2 student ID+ 300 KN 24 24 Diameter Last 2 student ID+ 15 mm Last 3 student ID+ 500 mm=L1 724 C B 24 Q=Last 2 student ID+ 100 KN 24 Diameter Last 2 student ID+ 40 mmarrow_forward
- Q2Two wooden members of uniform cross section are joined by the simple scarf splice shown. Knowing that the maximum allowable tensile stress in the glued splice is 75 psi, determine (a) the largest load P that can be safely supported, (b) the corresponding shearing stress in the splice. น Last 1 student ID+5 inch=W =9 4 L=Last 1 student ID+8 inch =12 60° P'arrow_forwardQ4 The two solid shafts are connected by gears as shown and are made of a steel for which the allowable shearing stress is 7000 psi. Knowing the diameters of the two shafts are, respectively, dBC determine the largest torque Tc that can be applied at C. 4 and dEF dBC=Last 1 student ID+3 inch dEF=Last 1 student ID+1 inch 7 R=Last 1 Student ID+5 inch 9 R B Tc 2.5 in. E TF Harrow_forwardExperiment تكنولوجيا السيارات - Internal Forced convenction Heat transfer Air Flow through Rectangular Duct. objective: Study the convection heat transfer of air flow through rectangular duct. Valve Th Top Dead Centre Exhaust Valve Class CP. N; ~ RIVavg Ti K 2.11 Te To 18.8 21.3 45.8 Nath Ne Pre Calculations:. Q = m cp (Te-Ti) m: Varg Ac Acca*b Q=hexp As (Ts-Tm) 2 2.61 18.5 20.846.3 Tm = Te-Ti = 25 AS-PL = (a+b)*2*L Nu exp= Re-Vavy D heep Dh k 2ab a+b Nu Dh the- (TS-Tm) Ts. Tmy Name / Nu exp Naxe بب ارتدان العشريarrow_forward
- Procedure:1- Cartesian system, 2D3D,type of support2- Free body diagram3 - Find the support reactions4- If you find a negativenumber then flip the force5- Find the internal force3D∑Fx=0∑Fy=0∑Fz=0∑Mx=0∑My=0\Sigma Mz=02D\Sigma Fx=0\Sigma Fy=0\Sigma Mz=05- Use method of sectionand cut the elementwhere you want to findarrow_forwardProcedure:1- Cartesian system, 2D3D,type of support2- Free body diagram3 - Find the support reactions4- If you find a negativenumber then flip the force5- Find the internal force3D∑Fx=0∑Fy=0∑Fz=0∑Mx=0∑My=0\Sigma Mz=02D\Sigma Fx=0\Sigma Fy=0\Sigma Mz=05- Use method of sectionand cut the elementwhere you want to findthe internal force andkeep either side of thearrow_forwardProcedure: 1- Cartesian system, 2D3D, type of support 2- Free body diagram 3 - Find the support reactions 4- If you find a negative number then flip the force 5- Find the internal force 3D ∑Fx=0 ∑Fy=0 ∑Fz=0 ∑Mx=0 ∑My=0 ΣMz=0 2D ΣFx=0 ΣFy=0 ΣMz=0 5- Use method of section and cut the element where you want to find the internal force and keep either side of thearrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Refrigeration and Air Conditioning Technology (Mi...Mechanical EngineeringISBN:9781305578296Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill JohnsonPublisher:Cengage Learning

Refrigeration and Air Conditioning Technology (Mi...
Mechanical Engineering
ISBN:9781305578296
Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson
Publisher:Cengage Learning
Thermodynamic Availability, What is?; Author: MechanicaLEi;https://www.youtube.com/watch?v=-04oxjgS99w;License: Standard Youtube License