Question

A 0.500-inch diameter aluminum bar is subjected to a force of 2500 lb. The engineering stress in pounds per square inch (psi) on the bar is:

• A. 12, 700 psi
• B. 16, 700 psi
• C. 18, 700 psi
• D. 20, 700 psi

Hint:

Always use consistent units when calculating stress. Convert diameters to area using A = π(d/2)^2 for circular cross-sections.

Answer 1

The Correct Option is A

\(\sigma = \frac{F}{A}\)
To calculate, F = 2500 lb and A is determined using `\(\pi (\frac{d}{2})^2\)` with d = 0.500 in, yielding `\(\pi (\frac{0.500}{2})^2\)` in`\(^2\)`.
\(A \approx 0.196 \text{ in}^2, \quad \sigma = \frac{2500}{0.196} \approx 12,700 \text{ psi}\)