Question

The resistivity of a material is $S$ ohm meter. The resistance between opposite faces of a solid cube of edge $10cm$ is ( in ohm)

• A. $\frac{S}{2}$
• B. $\frac{S}{10}$
• C. $100S$
• D. $10S$

Answer 1

The correct option is D $10S$

$R=\frac{\rho l}{A}$

Area $=(0.1{)}^2$

$dR=\frac{Sdx}{0.01}$

$\int dR=100S{\int }_0^{0.1}dx$

$R=100S\left(0.1\right)$

$R=10S$