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Calculate σ_x for r_i = 1 cm

Remember elementary statics? It gives the bending stress at point O as

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Using my calculator, I get σ_x=-101.7 MPa. We'll check the MATLAB result against this value.

Calculate σ_x at point O

In your program, leave a blank line and start a new section for calculating σ_x at point O with an explanatory comment line. Then, create the parameters M, ro, and ri since these are needed to calculate σ_x.

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The factor 10^-6^ above converts the result into MPa. The semi-colon at the end of the line is left off so that we can see what the resulting value of sigma_x is. Click on the Run icon in the editor (or hit the F5 key) . What is the value of sigma_x reported by your program? I get

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This is close enough to my paper-and-pencil result of -101.7 MPa above. See my beam.m entire program here (opens in a new windowright click and select save target as, or just left-click and copy-paste in the editor).

Go to Step 3: Plot σ_x vs. r_iSee and rate the complete Learning Module

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