Explanation

(a) $a = 1,b = 2,c = 3$
$\Rightarrow R_{\max} = \frac{\rho.L}{A} = \frac{\rho.c}{a.b}$
[image:3_image162.png]
$R_{\min} = \frac{\rho.L''}{A''} = \frac{\rho.a}{b.c}$
$\Rightarrow \frac{R_{\max}}{R_{\min}} = \frac{\frac{\rho.c}{a.b}}{\frac{\rho.a}{b.c}} = \frac{c}{a} \times \frac{c}{a} \Rightarrow \frac{c^{2}}{a^{2}} = \left( \frac{c}{a} \right)^{2} = \left( \frac{3}{1} \right)^{2} = \frac{9}{1}$