Question

One end of uniform wire of length $L$ and of weight $W$ is attached rigidly to a point in the roof and a weight $W_1$ is suspended from the lower end. If $A$ is the area of cross-section of the wire, the stress in the wire at a height $\frac{3L}{4}$ from its lower end is:

• A. $\frac{W_1}{A}$
• B. $\frac{(W_1+\frac{W}{4})}{A}$
• C. $\frac{(W_1+\frac{3W}{4})}{A}$
• D. $\frac{W_1+W}{A}$

Answer 1

The correct option is C $\frac{(W_1+\frac{3W}{4})}{A}$

$stress=\frac{Tension}{Area}$
Tension at height $\frac{3L}{4}$ from lower end
is $\frac{3}{4}w+w_1$
So, stress$=\frac{\frac{3}{4}w+w_1}{S}$