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

Options

A. 8
B. 4
C. 2
D. None of these

Answer

B

Explanation

Let the length of varous edges in increasing order be `l, x, 2l`, respectively.

Maximumm resistance, `R_("max")=(rho 2l)/(x l)=(2rho)/(x)`
and minimum resistance, `R_("min")=(rho l)/(2l x)=(rho)/(2x)`
`therefore " " (R_("max"))/(R_("min"))=(2)/(1//2)=4`