Heat and Mass Transfer: Fundamentals and Applications
5th Edition
ISBN: 9780073398181
Author: Yunus A. Cengel Dr., Afshin J. Ghajar
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 3, Problem 213P
Two finned surfaces with long fins are identical, except that the convection heat transfer coefficient for the first finned surface is twice that of the second one. Which of the following conditions is accurate for the efficiency and effectiveness of the first finned surface relative to the second one?
(a) Higher efficiency and higher effectiveness
(b) Higher efficiency but lower effectiveness
(c) Lower efficiency but higher effectiveness
(ci) Lower efficiency and lower effectiveness
(e) Equal efficiency and equal effectiveness
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Note:
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Question:
4. Block A and B are two different pieces of wood. Determine the minimum dimension for
"a", if the shear stress of the wood is 50Mpa. The thickness of the wood is 30cm.
600N
A
Chapter 3 Solutions
Heat and Mass Transfer: Fundamentals and Applications
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