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Fundamentals of Engineering Thermodynamics
8th Edition
ISBN: 9781118412930
Author: Michael J. Moran, Howard N. Shapiro, Daisie D. Boettner, Margaret B. Bailey
Publisher: WILEY
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Question
Chapter 2.7, Problem 38CU
To determine
To determine true or false:
The heat transfer coefficient, h, in Newton’s law of cooling is not a
Expert Solution & Answer
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Note : Exam is open notes &tables / Answer all questions.
Q.1. The press shown for Figure.1 has a rated load
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Problem 2 (55 pts). We now consider the FEM solution of Problem 1.(a) [5pts] Briefly describe the 4 steps necessary to obtain the approximate solution of thatBVP using the Galerkin FEM. Use the minimum amount of math necessary to supportyour explanations.(b) [20pts] Derive the weak form of the BVP.(c) [10pts] Assuming a mesh of two equal elements and linear shape functions, sketch byhand how you expect the FEM solution to look like. Also sketch the analytical solutionfor comparison. In your sketch, identify the nodal degrees of freedom that the FEMsolution seeks to find.(d) [10pts] By analogy with the elastic rod problem and heat conduction problem considered in class, write down the stiffness matrix and force vector for each of the twoelements considered in (c).(e) [10pts] Assemble the global system of equations, and verbally explain how to solve it.
An aluminum rod of length L = 1m has mass density ρ = 2700 kgm3 andYoung’s modulus E = 70GPa. The rod is fixed at both ends. The exactnatural eigenfrequencies of the rod are ωexactn =πnLqEρfor n=1,2,3,. . . .1. What is the minimum number of linear elements necessary todetermine the fundamental frequency ω1 of the system? Discretizethe rod in that many elements of equal length, assemble the globalsystem of equations KU = ω2MU, and find the fundamentalfrequency ω1. Compute the relative error e1 = (ω1 − ωexact1)/ωexact1.Sketch the fundamental mode of vibration.
Chapter 2 Solutions
Fundamentals of Engineering Thermodynamics
Ch. 2.7 - Prob. 1ECh. 2.7 - 2. What are several things you as an individual...Ch. 2.7 - 3. How does the kilowatt-hour meter in your house...Ch. 2.7 - 4. Why is it incorrect to say that a system...Ch. 2.7 - Prob. 5ECh. 2.7 - Prob. 6ECh. 2.7 - 7. When microwaves are beamed onto a tumor during...Ch. 2.7 - 8. For good acceleration, what is more important...Ch. 2.7 - 9. Experimental molecular motors are reported to...Ch. 2.7 - 10. For polytropic expansion or compression, what...
Ch. 2.7 - Prob. 11ECh. 2.7 - Prob. 12ECh. 2.7 - 13. What form does the energy balance take for an...Ch. 2.7 - 14. What forms of energy and energy transfer are...Ch. 2.7 - Prob. 15ECh. 2.7 - 16. Steve has a pedometer that reads kilocalories...Ch. 2.7 - Prob. 17ECh. 2.7 - Prob. 1CUCh. 2.7 - Prob. 11CUCh. 2.7 - Prob. 12CUCh. 2.7 - Prob. 13CUCh. 2.7 - Prob. 14CUCh. 2.7 - 15. In mechanics, the work of a resultant force...Ch. 2.7 - 16. What direction is the net energy transfer by...Ch. 2.7 - 17. The differential of work, δW, is said to be an...Ch. 2.7 - Prob. 18CUCh. 2.7 - Prob. 19CUCh. 2.7 - Prob. 20CUCh. 2.7 - Prob. 21CUCh. 2.7 - Prob. 22CUCh. 2.7 - Prob. 23CUCh. 2.7 - Prob. 24CUCh. 2.7 - Prob. 25CUCh. 2.7 - 26. State the sign convention used in...Ch. 2.7 - Prob. 27CUCh. 2.7 - Prob. 28CUCh. 2.7 - Prob. 29CUCh. 2.7 - 30. Based on the mechanisms of heat transfer, list...Ch. 2.7 - Prob. 31CUCh. 2.7 - Prob. 32CUCh. 2.7 - 33. The total energy of a closed system can change...Ch. 2.7 - 34. The energy of an isolated system can only...Ch. 2.7 - 35. If a closed system undergoes a thermodynamic...Ch. 2.7 - Prob. 36CUCh. 2.7 - Prob. 37CUCh. 2.7 - Prob. 38CUCh. 2.7 - Prob. 39CUCh. 2.7 - Prob. 40CUCh. 2.7 - Prob. 41CUCh. 2.7 - 42. A process that is adiabatic cannot involve...Ch. 2.7 - Prob. 43CUCh. 2.7 - Prob. 44CUCh. 2.7 - Prob. 45CUCh. 2.7 - Prob. 46CUCh. 2.7 - 47. A rotating flywheel stores energy in the form...Ch. 2.7 - Prob. 48CUCh. 2.7 - Prob. 49CUCh. 2.7 - 50. If a closed system undergoes a process for...Ch. 2.7 - Prob. 51CUCh. 2.7 - Prob. 52CUCh. 2.7 - Prob. 53CUCh. 2.7 - Prob. 54CUCh. 2.7 - 2.1 A baseball has a mass of 0.3 lb. What is the...Ch. 2.7 - 2.2 Determine the gravitational potential energy,...Ch. 2.7 - 2.3 An object whose weight is 100 lbf experiences...Ch. 2.7 - 2.4 A construction crane weighing 12.000 lbf fell...Ch. 2.7 - 2.5 An automobile weighing 2500 lbf increases its...Ch. 2.7 - 2.6 An object of mass 1000 kg, initially having a...Ch. 2.7 - 2.7 A 30-seat turboprop airliner whose mass is...Ch. 2.7 - 2.8 An automobile having a mass of 900 kg...Ch. 2.7 - 2.9 Vehicle crumple zones are designed to absorb...Ch. 2.7 - 2.10 An object whose mass is 300 lb experiences...Ch. 2.7 - Prob. 11PCh. 2.7 - 2.12 Using KE = Iω2/2 from Problem 2.11a, how fast...Ch. 2.7 - 2.13 Two objects having different masses are...Ch. 2.7 - 2.14 An object whose mass is 100 lb falls freely...Ch. 2.7 - 2.15 During the packaging process, a can of soda...Ch. 2.7 - 2.16 Beginning from rest, an object of mass 200 kg...Ch. 2.7 - 2.17 Jack, who weighs 150 lbf, runs 5 miles in 43...Ch. 2.7 - 2.18 An object initially at an elevation of 5 m...Ch. 2.7 - 2.19 An object of mass 10 kg, initially at rest,...Ch. 2.7 - 2.20 An object initially at rest experiences a...Ch. 2.7 - 2.21 The drag force, Fd, imposed by the...Ch. 2.7 - 2.22 A major force opposing the motion of a...Ch. 2.7 - 2.23 The two major forces opposing the motion of a...Ch. 2.7 - 2.24 Measured data for pressure versus volume...Ch. 2.7 - 2.25 Measured data for pressure versus volume...Ch. 2.7 - 2.26 A gas in a piston-cylinder assembly undergoes...Ch. 2.7 - 2.27 Carbon dioxide (CO2) gas within a...Ch. 2.7 - 2.28 A gas in a piston-cylinder assembly undergoes...Ch. 2.7 - 2.29 Nitrogen (N2) gas within a piston-cylinder...Ch. 2.7 - 2.30 Oxygen (O2) gas within a piston-cylinder...Ch. 2.7 - 2.31 A closed system consisting of 14.5 lb of air...Ch. 2.7 - 2.32 Air contained within a piston-cylinder...Ch. 2.7 - 2.33 A gas contained within a piston-cylinder...Ch. 2.7 - 2.34 Carbon monoxide gas (CO) contained within a...Ch. 2.7 - 2.35 Air contained within a piston-cylinder...Ch. 2.7 - 2.36 The belt sander shown in Fig. P2.36 has a...Ch. 2.7 - 2.37 A 0.15-m-diameter pulley turns a belt...Ch. 2.7 - 2.38 A 10-V battery supplies a constant current of...Ch. 2.7 - 2.39 An electric heater draws a constant current...Ch. 2.7 - 2.40 A car magazine article states that the power...Ch. 2.7 - 2.41 The pistons of a V-6 automobile engine...Ch. 2.7 - 2.42 Figure P2.42 shows an object whose mass is 5...Ch. 2.7 - Prob. 43PCh. 2.7 - 2.44 A soap film is suspended on a wire frame, as...Ch. 2.7 - 2.45 As shown in Fig. P2.45, a spring having an...Ch. 2.7 - 2.46 A fan forces air over a computer circuit...Ch. 2.7 - 2.47 As shown in Fig. P2.47, the 6-in.-thick...Ch. 2.7 - 2.48 As shown in Fig. P2.48, an oven wall consists...Ch. 2.7 - 2.49 A composite plane wall consists of a...Ch. 2.7 - 2.50 A composite plane wall consists of a...Ch. 2.7 - 2.51 An insulated frame wall of a house has an...Ch. 2.7 - 2.52 Complete the following exercise using heat...Ch. 2.7 - Prob. 53PCh. 2.7 - Prob. 54PCh. 2.7 - 2.55 The outer surface of the grill hood shown in...Ch. 2.7 - 2.56 Each line of the following table gives data...Ch. 2.7 - 2.57 Each line of the following table gives data,...Ch. 2.7 - 2.58 A closed system of mass 10 kg undergoes a...Ch. 2.7 - Prob. 59PCh. 2.7 - 2.60 A gas contained in a piston−cylinder assembly...Ch. 2.7 - 2.61 A gas contained within a piston−cylinder...Ch. 2.7 - 2.62 An electric motor draws a current of 10 amp...Ch. 2.7 - 2.63 As shown in Fig. P2.63, the outer surface of...Ch. 2.7 - 2.64 One kg of Refrigerant 22, initially at p1 =...Ch. 2.7 - 2.65 A gas is contained in a vertical...Ch. 2.7 - 2.66 A gas undergoes a process in a...Ch. 2.7 - 2.67 Four kilograms of carbon monoxide (CO) is...Ch. 2.7 - 2.68 Helium gas is contained in a closed rigid...Ch. 2.7 - 2.69 Steam in a piston−cylinder assembly undergoes...Ch. 2.7 - 2.70 Air expands adiabatically in a...Ch. 2.7 - 2.71 A vertical piston−cylinder assembly with a...Ch. 2.7 - 2.72 Gaseous CO2 is contained in a vertical...Ch. 2.7 - 2.73 Figure P2.73 shows a gas contained in a...Ch. 2.7 - 2.74 The following table gives data, in kJ, for a...Ch. 2.7 - 2.75 The following table gives data, in Btu, for a...Ch. 2.7 - 2.76 Figure P2.76 shows a power cycle executed by...Ch. 2.7 - 2.77 A gas within a piston−cylinder assembly...Ch. 2.7 - 2.78 A gas within a piston-cylinder assembly...Ch. 2.7 - 2.79 A gas undergoes a cycle in a piston-cylinder...Ch. 2.7 - 2.80 As shown in Fig. P2.80, a gas within a...Ch. 2.7 - Prob. 81PCh. 2.7 - Prob. 82PCh. 2.7 - Prob. 83PCh. 2.7 - Prob. 84PCh. 2.7 - 2.85 A concentrating solar collector system, as...Ch. 2.7 - Prob. 86PCh. 2.7 - Prob. 87PCh. 2.7 - Prob. 88PCh. 2.7 - 2.89 A refrigeration cycle operating as shown in...Ch. 2.7 - Prob. 90PCh. 2.7 - Prob. 91PCh. 2.7 - Prob. 92PCh. 2.7 - Prob. 93PCh. 2.7 - Prob. 94PCh. 2.7 - 2.95 A heat pump maintains a dwelling at 688F....Ch. 2.7 - 2.96 A heat pump cycle delivers energy by heat...
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- Problem 1 (65 pts, suggested time 50 mins). An elastic string of constant line tension1T is pinned at x = 0 and x = L. A constant distributed vertical force per unit length p(with units N/m) is applied to the string. Under this force, the string deflects by an amountv(x) from its undeformed (horizontal) state, as shown in the figure below.The PDE describing mechanical equilibrium for the string isddx Tdvdx− p = 0 . (1)(a) [5pts] Identify the BCs for the string and identify their type (essential/natural). Writedown the strong-form BVP for the string, including PDE and BCs.(b) [10pts] Find the analytical solution of the BVP in (a). Compute the exact deflectionof the midpoint v(L/2).(c) [15pts] Derive the weak-form BVP.(d) [5pts] What is the minimum number of linear elements necessary to compute the deflection of the midpoint?(e) [15pts] Write down the element stiffness matrix and the element force vector for eachelement.arrow_forwardProblem 1 (35 pts). An elastic string of constant line tension1 T is pinned at x = 0 andx = L. A constant distributed vertical force per unit length p (with units N/m) is appliedto the string. Under this force, the string deflects by an amount v(x) from its undeformed(horizontal) state, as shown in the figure below.Force equilibrium in the string requires thatdfdx − p = 0 , (1)where f(x) is the internal vertical force in the string, which is given byf = Tdvdx . (2)(a) [10pts] Write down the BVP (strong form) that the string deflection v(x) must satisfy.(b) [2pts] What order is the governing PDE in the BVP of (a)?(c) [3pts] Identify the type (essential/natural) of each boundary condition in (a).(d) [20pts] Find the analytical solution of the BVP in (a).arrow_forwardProblem 2 (25 pts, (suggested time 15 mins). An elastic string of line tension T andmass per unit length µ is pinned at x = 0 and x = L. The string is free to vibrate, and itsfirst vibration mode is shown below.In order to find the frequency of the first mode (or fundamental frequency), the string isdiscretized into a certain number of linear elements. The stiffness and mass matrices of thei-th element are, respectivelyESMi =TLi1 −1−1 1 EMMi =Liµ62 11 2 . (2)(a) [5pts] What is the minimum number of linear elements necessary to compute the fundamental frequency of the vibrating string?(b) [20pts] Assemble the global eigenvalue problem and find the fundamental frequency ofvibration of the stringarrow_forward
- I need part all parts please in detail (including f)arrow_forwardProblem 3 (10 pts, suggested time 5 mins). In class we considered the mutiphysics problem of thermal stresses in a rod. When using linear shape functions, we found that the stress in the rod is affected by unphysical oscillations like in the following plot E*(ux-a*T) 35000 30000 25000 20000 15000 10000 5000 -5000 -10000 0 Line Graph: E*(ux-a*T) MULT 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Arc length (a) [10pts] What is the origin of this issue and how can we fix it?arrow_forwardanswer the questions and explain all of it in words. Ignore where it says screencast and in class explanationarrow_forward
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