Question

A soil sampler has inner and outer radius of 26 mm and 30 mm respectively. The area ratio of the sampler is ?
(Rounded upto two decimal places).

• A. 28.15 %
• B. 33.14 %
• C. 2.06 %
• D. 42.19 %

Answer 1

The correct option is B 33.14 %

Given, $D_2=30mm,D_1=26mm$

Area ratio, $A_r=\frac{D_2^2-D_1^2}{D_1^2}\times 100$

$=\frac{{30}^2-{26}^2}{{26}^2}\times 100$
= 33.14 %