Question

Bring out clearly two differences between electric resistance and electric specific resistance.

Answer 1

Basis of Difference	Electric resistance	Electric specific resistance
1. Meaning	Electric resistance is the opposition offered by a conductor to the passage of drifting electrons through it.	Electric specific resistance is the resistance offered by a conductor of unit length and unit area of cross-section.
2. Dependence	Electric resistance depends on the material, length, area of cross-section and temperature of the conductor.	Electric specific resistance depends only on the material and temperature of the conductor.
3. Formula	Electric resistance is given by $$R = \rho \frac{l}{A}$$.	Electric specific resistance is given by $$\rho = \frac{RA}{l}$$.
4. SI unit	The SI unit of electric resistance is the ohm ($$\Omega$$).	The SI unit of electric specific resistance is ohm-meter ($$\Omega \text{ m}$$).
5. Effect of size	Electric resistance changes with the length and area of the cross-section of the conductor.	Electric specific resistance does not change with the shape or size of the conductor.