Question

The solidification time of a cube and a cylinder of the same material, produced through the same sand casting process, is found to be equal. Each side of the cube is $a$, and the radius and the length of the cylinder are $r$ and $4r$, respectively. If the solidification time is governed by Chvorinov's equation, then the ratio $\frac ra$ is

• A. $\frac {1}{3}$
• B. $\frac {5}{12}$
• C. $\frac {7}{12}$
• D. $\frac {5}{9}$

Answer 1

Answer: (B)

$\frac {5}{12}$

Answer 2

The correct option is (B): $\frac {5}{12}$.