Dimensions of a block are `1 cm xx 1cm xx 100cm`. If specific resistance of its material is `3 xx 10^(-7) ohm-m`, then the resistance between the opposite rectangular facesis

Options

A. `3xx10^(-9)` ohm
B. `3xx10^(-7)` ohm
C. `3xx10^(-8)` ohm
D. `3xx10^(-3)` ohm

Answer

B

Explanation

Length l=1 cm =`10^(-2)` m

Area of cross-section A = 1 cm × 100 cm
`=100 cm^2 =10^(-2) m^2`
Resistance `R=3xx10^(-7)xx10^(-2)/10^(-2)=3xx10^(-7)Omega`