Vector Mechanics for Engineers: Statics, 11th Edition
11th Edition
ISBN: 9780077687304
Author: Ferdinand P. Beer, E. Russell Johnston Jr., David Mazurek
Publisher: McGraw-Hill Education
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Chapter 5.4, Problem 5.121P
PROBLEM 5.121
The three legs of a small glass-topped table are equally spaced and are made of steel tubing, which has an outside diameter of 24 mm and a cross-sectional area of 150 mm2. The diameter and the thickness of the table top are 600 mm and 10 mm, respectively. Knowing that the density of steel is 7860 kg/m3 and of glass is 2190 kg/m3, locate the center of gravity of the table.
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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.
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Chapter 5 Solutions
Vector Mechanics for Engineers: Statics, 11th Edition
Ch. 5.1 - 5.1 through 5.9 Locate the centroid of the plane...Ch. 5.1 - 5.1 through 5.9 Locate the centroid of the plane...Ch. 5.1 - 5.1 through 5.9 Locate the centroid of the plane...Ch. 5.1 - Locate the centroid of the plane area shown.Ch. 5.1 - 5.1 through 5.9 Locate the centroid of the plane...Ch. 5.1 - Locate the centroid of the plane area shown.Ch. 5.1 - 5.1 through 5.9 Locate the centroid of the plane...Ch. 5.1 - Locate the centroid of the plane area shown.Ch. 5.1 - Locate the centroid of the plane area shown.Ch. 5.1 - Locate the centroid of the plane area shown.
Ch. 5.1 - 5.10 through 5.15 Locate the centroid of the plane...Ch. 5.1 - Locate the centroid of the plane area shown.Ch. 5.1 - 5.10 through 5.15 Locate the centroid of the plane...Ch. 5.1 - 5.10 through 5.15 Locate the centroid of the plane...Ch. 5.1 - 5.10 through 5.15 Locate the centroid of the plane...Ch. 5.1 - PROBLEM 5.16 Determine the y coordinate of the...Ch. 5.1 - Show that as r1 approaches r2, the location of the...Ch. 5.1 - Prob. 5.18PCh. 5.1 - For the semiannular area of Prob. 5.12, determine...Ch. 5.1 - Prob. 5.20PCh. 5.1 - Prob. 5.21PCh. 5.1 - The horizontal x-axis is drawn through the...Ch. 5.1 - PROBLEM 5.23 The first moment of the shaded area...Ch. 5.1 - Prob. 5.24PCh. 5.1 - Prob. 5.25PCh. 5.1 - Prob. 5.26PCh. 5.1 - A thin, homogeneous wire is bent to form the...Ch. 5.1 - The homogeneous wire ABC is bent into a...Ch. 5.1 - The frame for a sign is fabricated from thin, flat...Ch. 5.1 - The homogeneous wire ABCD is bent as shown and is...Ch. 5.1 - The homogeneous wire ABCD is bent as shown and is...Ch. 5.1 - Determine the distance h for which the centroid of...Ch. 5.1 - Knowing that the distance h has been selected to...Ch. 5.2 - 5.34 through 5.36 Determine by direct integration...Ch. 5.2 - 5.34 through 5.36 Determine by direct integration...Ch. 5.2 - 5.34 through 5.36 Determine by direct integration...Ch. 5.2 - 5.37 through 5.39 Determine by direct integration...Ch. 5.2 - 5.37 through 5.39 Determine by direct integration...Ch. 5.2 - 5.37 through 5.39 Determine by direct integration...Ch. 5.2 - 5.40 and 5.41 Determine by direct integration the...Ch. 5.2 - 5.40 and 5.41 Determine by direct integration the...Ch. 5.2 - Determine by direct integration the centroid of...Ch. 5.2 - 5.43 and 5.44 Determine by direct integration the...Ch. 5.2 - 5.43 and 5.44 Determine by direct integration the...Ch. 5.2 - 5.45 and 5.46 A homogeneous wire is bent into the...Ch. 5.2 - 5.45 and 5.46 A homogeneous wire is bent into the...Ch. 5.2 - A homogeneous wire is bent into the shape shown....Ch. 5.2 - 5.48 and 5.49 Determine by direct integration the...Ch. 5.2 - Prob. 5.49PCh. 5.2 - Determine the centroid of the area shown in terms...Ch. 5.2 - Determine the centroid of the area shown when a =...Ch. 5.2 - Prob. 5.52PCh. 5.2 - 5.53 Determine the volume and the surface area of...Ch. 5.2 - Determine the volume and the surface area of the...Ch. 5.2 - Prob. 5.55PCh. 5.2 - Prob. 5.56PCh. 5.2 - Verify that the expressions for the volumes of the...Ch. 5.2 - Knowing that two equal caps have been removed from...Ch. 5.2 - Three different drive belt profiles are to be...Ch. 5.2 - Determine the capacity, in liters, of the punch...Ch. 5.2 - Determine the volume and total surface area of the...Ch. 5.2 - Determine the volume and weight of the solid brass...Ch. 5.2 - Determine the total surface area of the solid...Ch. 5.2 - Prob. 5.64PCh. 5.2 - The shade for a wall-mounted light is formed from...Ch. 5.3 - 5.66 and 5.67 For the beam and loading shown,...Ch. 5.3 - 5.66 and 5.67 For the beam and loading shown,...Ch. 5.3 - Prob. 5.68PCh. 5.3 - 5.68 through 5.73 Determine the reactions at the...Ch. 5.3 - 5.68 through 5.73 Determine the reactions at the...Ch. 5.3 - 5.68 through 5.73 Determine the reactions at the...Ch. 5.3 - 5.68 through 5.73 Determine the reactions at the...Ch. 5.3 - 5.68 through 5.73 Determine the reactions at the...Ch. 5.3 - Determine (a) the distance a so that the vertical...Ch. 5.3 - Determine (a) the distance a so that the reaction...Ch. 5.3 - Prob. 5.76PCh. 5.3 - Prob. 5.77PCh. 5.3 - The beam AB supports two concentrated loads and...Ch. 5.3 - For the beam and loading of Prob. 5.78, determine...Ch. 5.3 - The cross section of a concrete dam is as shown....Ch. 5.3 - The cross section of a concrete dam is as shown....Ch. 5.3 - The dam for a lake is designed to withstand the...Ch. 5.3 - The base of a dam for a lake is designed to resist...Ch. 5.3 - 5.84 An automatic valve consists of a 9 × 9-in....Ch. 5.3 - Prob. 5.85PCh. 5.3 - The 3 4-m side AB of a tank is hinged at its...Ch. 5.3 - The 3 4-m side of an open tank is hinged at its...Ch. 5.3 - A 0.5 0.8-m gate AB is located at the bottom of a...Ch. 5.3 - A 0.5 0.8-m gate AB is located at the bottom of a...Ch. 5.3 - A 4 2-ft gate is hinged at A and is held in...Ch. 5.3 - Fig. P5.90 5.91 Solve Prob. 5.90 if the gate...Ch. 5.3 - A prismatically shaped gate placed at the end of a...Ch. 5.3 - A prismatically shaped gate placed at the end of a...Ch. 5.3 - A long trough is supported by a continuous hinge...Ch. 5.3 - The square gate AB is held in the position shown...Ch. 5.4 - Consider the composite body shown. Determine (a)...Ch. 5.4 - Prob. 5.97PCh. 5.4 - Prob. 5.98PCh. 5.4 - Prob. 5.99PCh. 5.4 - Prob. 5.100PCh. 5.4 - Prob. 5.101PCh. 5.4 - Prob. 5.102PCh. 5.4 - Prob. 5.103PCh. 5.4 - For the machine element shown, locate the y...Ch. 5.4 - For the machine element shown, locate the x...Ch. 5.4 - 5.106 and 5.107 Locate the center of gravity of...Ch. 5.4 - 5.106 and 5.107 Locate the center of gravity of...Ch. 5.4 - A corner reflector for tracking by radar has two...Ch. 5.4 - A wastebasket, designed to fit in the corner of a...Ch. 5.4 - An elbow for the duct of a ventilating system is...Ch. 5.4 - A window awning is fabricated from sheet metal...Ch. 5.4 - Prob. 5.112PCh. 5.4 - Prob. 5.113PCh. 5.4 - A thin steel wire with a uniform cross section is...Ch. 5.4 - The frame of a greenhouse is constructed from...Ch. 5.4 - Locate the center of gravity of the figure shown,...Ch. 5.4 - Prob. 5.117PCh. 5.4 - A scratch awl has a plastic handle and a steel...Ch. 5.4 - PROBLEM 5.117 A bronze bushing is mounted inside a...Ch. 5.4 - PROBLEM 5.120 A brass collar, of length 2.5 in.,...Ch. 5.4 - PROBLEM 5.121 The three legs of a small...Ch. 5.4 - Prob. 5.122PCh. 5.4 - Determine by direct integration the values of x...Ch. 5.4 - Prob. 5.124PCh. 5.4 - PROBLEM 5.125 Locate the centroid of the volume...Ch. 5.4 - Prob. 5.126PCh. 5.4 - Prob. 5.127PCh. 5.4 - PROBLEM 5.128 Locate the centroid of the volume...Ch. 5.4 - PROBLEM 5.129 Locate the centroid of the volume...Ch. 5.4 - Show that for a regular pyramid of height h and n...Ch. 5.4 - PROBLEM 5.131 Determine by direct integration the...Ch. 5.4 - PROBLEM 5.132 The sides and the base of a punch...Ch. 5.4 - Locate the centroid of the section shown, which...Ch. 5.4 - Locate the centroid of the section shown, which...Ch. 5.4 - Determine by direct integration the location of...Ch. 5.4 - Alter grading a lot, a builder places four stakes...Ch. 5 - 5.137 and 5.138 Locate the centroid of the plane...Ch. 5 - 5.137 and 5.138 Locate the centroid of the plane...Ch. 5 - Prob. 5.139RPCh. 5 - Determine by direct integration the centroid of...Ch. 5 - Determine by direct integration the centroid of...Ch. 5 - The escutcheon (a decorative plate placed on a...Ch. 5 - Determine the reactions at the supports for the...Ch. 5 - A beam is subjected to a linearly distributed...Ch. 5 - A tank is divided into two sections by a 1 1-m...Ch. 5 - Determine the y coordinate of the centroid of the...Ch. 5 - An 8-in.-diameter cylindrical duct and a 4 8-in....Ch. 5 - Three brass plates are brazed to a steel pipe to...
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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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