Question

Specific resistance is numerically equal to the resistance offered by :

• A. 1 cm length of a conductor
• B. A conductor of unit cross-section
• C. 1 cm length of a conductor of 1 $c{m}^2$ of cross-section
• D. 1 $c{m}^3$ of a conductor

Answer 1

Answer: (C)

1 cm length of a conductor of 1 $c{m}^2$ of cross-section

Specific resistance $\rho =\frac{RA}{l}$
For $\rho =R$
$A=1m^2$ or $1c{m}^2,1=1m;1cm$
$\therefore$ Specific resistance is numeracally equal to resistance offered by 1 $cm$ length of a conductor of 1 $c{m}^2$ of cross section.