Concept explainers
The expression of R for a circular cross section.
Answer to Problem 187P
The expression of R for a circular cross section is
Explanation of Solution
Consider w be the width as a function of
Sketch the cross section for the polar coordinate as shown in Figure 1.
Refer to Figure 1.
The distance
Differentiate both sides with respect to
Calculate the area of the strip
Substitute
Substitute
Integrate both sides of the Equation.
Calculate the area of the circle
Calculate the expression of
Substitute
Therefore, the expression of R for a circular cross section is
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Chapter 4 Solutions
Mechanics of Materials, 7th Edition
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