Calculate σ_x for r_i

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= 1 cm

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

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

Calculate

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σ_x at point O

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

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Following this is the statement to calculate I, the moment of inertia:

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Things to note: the parameter pi is predefined and contains a very accurate value of π. The operator ^ is used to raise a quantity to a desired power. Now we can calculate σx σ_x at O:

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The factor 1010^-6 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 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 σx σ_x vs. ri r_i

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