$$\sigma \approx 159.15 \text{ N/mm}^2$$ How To Fix - Unable To Load Vgcore Error Code 127 New
Substitute the force and area: $$\sigma = \frac{50,000 \text{ N}}{314.16 \text{ mm}^2}$$ Statistical Analysis Of Medical Data Using Sas.pdf
Substitute the diameter: $$A = \frac{\pi}{4} (20 \text{ mm})^2$$ $$A = \frac{\pi}{4} (400 \text{ mm}^2)$$ $$A \approx 314.16 \text{ mm}^2$$
The formula for average normal stress is: $$\sigma = \frac{P}{A}$$
Because "11 r" is likely a typo (perhaps you meant Problem , 1-11 , or a problem from Chapter 11 ), I have provided one of the most fundamental example problems found in Chapter 1 of that edition.