Question

Let a wire be suspended from the ceiling (rigid support) and stretched by a weight W attached at its free end. The longitudinal stress at any point of cross-sectional area A of the wire is:

• A. Zero
• B. $\frac{2W}{A}$
• C. $\frac{W}{A}$
• D. $\frac{W}{2A}$

Answer 1

Answer: (C)

$\frac{W}{A}$

Answer 2

The longitudinal stress at any point of cross-sectional area A of the wire is $\frac{W}{A}$.

Stress is defined as the force acting on a material per unit area. In this case, the force acting on the wire is the weight W, and the cross-sectional area of the wire is A. Therefore, the stress can be calculated as stress = force/area.

In this scenario, the weight W is acting downward, creating tension in the wire. The force is distributed over the cross-sectional area A, so the stress is $\frac{W}{A}$.