Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470501979
Author: Frank P. Incropera, David P. DeWitt, Theodore L. Bergman, Adrienne S. Lavine
Publisher: Wiley, John & Sons, Incorporated
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Chapter 12, Problem 12.42P
A sphere is suspended in air in a dark room and maintained at a uniform incandescenttemperature. When first viewed with the naked eye, the sphere appears to be brighter around the rim. After several hours, however, it appears to be brighter in the center. Of what type mate- rial would you reason the sphere is made? Give plausible reasons for the nonuniformity of brightness of the sphere and for the changing appearance with time.
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For the beam and loading shown, (a) draw the shear and bending moment diagrams, (b) determine the magnitude and location of the maximum absolute value of the bending momentConsider A = 0please show step by step process, i did something wrong with bending moment diagram( length of beam = 2 + 6 + 2)
CORRECT ANSWER ONLY WITH COMPLETE FBD. PREFERABLY HANDWRITTEN. I WILL UPVOTE
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Chapter 12 Solutions
Fundamentals of Heat and Mass Transfer
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A procedure for measuring the thermal conductivity...Ch. 12 - One scheme for extending the operation of gas...Ch. 12 - The equipment for heating a wafer during a...Ch. 12 - Neglecting the effects of radiation absorption,...Ch. 12 - Consider the evacuated tube solar collector...Ch. 12 - Solar flux of 900W/m2 is incident on the top side...Ch. 12 - Consider an opaque, gray surface whose directional...Ch. 12 - A contractor must select a roof covering material...Ch. 12 - It is not uncommon for the night sky temperature...Ch. 12 - Plant leaves possess small channels that connect...Ch. 12 - In the central receiver concept of solar energy...Ch. 12 - Radiation from the atmosphere or sky can be...Ch. 12 - A thin sheet of glass is used on the roof of a...Ch. 12 - Growers use giant fans to prevent grapes from...Ch. 12 - A circular metal disk having a diameter of 0.4 m...Ch. 12 - The neighborhood cat likes to sleep on the roof of...Ch. 12 - The exposed surface of a power amplifier for an...Ch. 12 - Consider a thin opaque, horizontal plate with an...Ch. 12 - The oxidized-aluminum wing of an aircraft has a...Ch. 12 - Two plates, one with a black painted surface and...Ch. 12 - A radiator on a proposed satellite solar power...Ch. 12 - A radiator on a proposed satellite solar power...Ch. 12 - A spherical satellite in near-earth orbit is...Ch. 12 - An annular fin of thickness t is used as a...Ch. 12 - The directional absorptivity of a gray surface...Ch. 12 - Two special coatings are available for application...Ch. 12 - Consider the spherical satellite of Problem...Ch. 12 - A spherical capsule of 3-m radius is fired from a...Ch. 12 - Consider the spherical satellite of Problem...Ch. 12 - A solar panel mounted on a spacecraft has an area...Ch. 12 - It is known that on clear nights a thin layer of...Ch. 12 - A shallow layer of water is exposed to the natural...Ch. 12 - A roof-cooling system, which operates by...Ch. 12 - A wet towel hangs on a clothes line under...Ch. 12 - Our students perform a laboratory experiment to...
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- CORRECT ANSWER AND COMPLETE FBD ONLY. I PREFER HANDWRITTEN BUT ITS OKAY IF NOT. I WILL UPVOTE 2. The space truss shown is supported by ball-and-socket joints at A, B and C. Factored loads P1 and P2 areacting on joints D and E, respectively, towards the negative y-direction. 1. Calculate the stress of member CE, indicate tension or compression. Answer: 23.61 MPa Tension2. Calculate the stress of member AD, indicate tension or compression. Answer: 21.01 MPa Compression3. Calculate the stress of member CD, indicate tension or compression. Answer: 11.03 MPa Tensionarrow_forwardCORRECT ANSWER AND COMPLETE FBD ONLY. I PREFER HANDWRITTEN BUT ITS OKAY IF NOT. I WILL UPVOTE 3. The frame has pin supports at A and E, subject to a wind load. Treat joint C to be an internal hinge. Given:Dimensions, H1 = 3.0 m; H2 = 4.5 m; L = 10.0 mWind loads, wWL (AB) = 4.8 kN/m; wWL (BC) = 3.9 kN/m; wWL (CD) = 1.5 kN/m; wWL (DE) = 1.2 kN/mMembers are made of A36 steel Wide Flange Section with the following properties:Area, A = 64000 mm2Depth, d = 762 mmFlange width, bf = 371 mmThickness of web, tw = 32 mmThickness of flange, tf = 57.9 mmMoment of inertia about x-axis, Ix = 6080 x 106 mm4The wide flange is oriented so that the bending is about the x-axis1. Calculate the stress in member AB, due to the axial load it carries, indicate if tension or compression.Answer: 0.0476 MPa Tension2. Calculate the stress in member DE, due to the axial load it carries, indicate if tension or compression.Answer: 0.2351 MPa Compression3. Calculate the maximum bending stress at B. Answer: 4.282 MPaarrow_forward32 mm 32 mm b' c' C 32 mm 32 mm b PROBLEM 6.41 a The extruded beam shown has a uniform wall thickness of 3 mm. Knowing that the vertical shear in the beam is 9 kN, determine the shearing stress at each of the five points indicated.arrow_forward
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According to your analysis, where is the point of interest to evaluate the safety factor among A, B, C, and D? Describe the reason. (Hint: To find F, the torque Tд is generated by the tangential force of F (i.e. Ftangential-Fcos20°) When n=2.5, K=1.8, and K₁ =1.3, determine the diameter of the shaft based on (2) static analysis using DE theory (note that fatigue stress concentration factors need to be used for this question because the loading condition is fatigue) and (3) a fatigue analysis using modified Goodman. Note) A standard diameter is not required for the questions. 10 in Darrow_forward3 N2=28 P(diametral pitch)=8 for all gears Coupled to 25 hp motor N3=34 Full depth spur gears with pressure angle=20° N₂=2000 rpm (1) Compute the circular pitch, the center-to-center distance, and base circle radii. (2) Draw the free body diagram of gear 3 and show all the forces and the torque. (3) In mounting gears, the center-to-center distance was reduced by 0.1 inch. 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