Question

The upper end of a wire of length 2 m and radius 2 mm is clamped. The lower end is twisted through an angle of $45^\circ$. The angle of shear is:

• A. 0.09°
• B. 0.045°
• C. 0.9°
• D. 4.5°

Answer 1

Answer: (B)

0.045°

Answer 2

$$\theta = \frac{r}{L}\times \theta_{\text{total}}$$

Here, $r=0.002\, \text{m}$, $L=2\, \text{m}$ and $\theta_{\text{total}}=45^\circ$. Thus,

$$\theta = \frac{0.002}{2} \times 45^\circ = 0.001 \times 45^\circ = 0.045^\circ.$$