Question

The external and internal radius of a hollow cylinder are to be measured to be (4.23 $\pm$ 0.01)cm and (3.89 $\pm$ 0.01)cm. The thickness of the wall of the cylinder is :

• A. (0.34 $\pm$ 0.02) cm
• B. (0.17 $\pm$ 0.02)cm
• C. (0.17 $\pm$ 0.00)cm
• D. (0.34 $\pm$ 0.00)cm

Answer 1

The correct option is A (0.34 $\pm$ 0.02) cm

Thickness $=R_{ext}-R_{int}=4.23-3.89=0.34$

Now, $\Delta Thickness=(\Delta R_{ext}/R_{ext}+\Delta R_{int}/R_{int})\times Thickness=0.02$