Question

All the edges of a block with parallel faces are unequal. Its largest edge is twice its shortest edge. The ratio of the maximum to the minimum resistance between parallel faces is

• A. $8$
• B. $4$
• C. $2$
• D. $1$

Answer 1

Answer: (B)

Let the length of various edges in increasing order be $l,x,2l$ respectively
$R_{m a x}=\frac{\rho 2 l}{x l}=\frac{2 \rho }{x};R_{m i n}=\frac{\rho l}{2 l x}=\frac{\rho }{2 x}$
$\therefore \, \, \frac{R_{m a x}}{R_{m i n}}=4$