Question

Dimensions of a metal block The ratio of $100cm\times 2cm\times 2cm$ resistances between square faces and rectangular faces is

• A. 1 : 1
• B. 25 : 1
• C. 2500:1
• D. 50 : 1

Answer 1

Answer: (C)

2500:1

$R_S=\frac{\rho \times 100}{4}$

$R_R=\frac{\rho \times 2}{100\times 2}=\frac{\rho }{100}$

$\frac{R_S}{R_R}=\frac{100\times 100}{4}=\frac{2500}{1}$