Question

Factors on which the specific resistance of a wire depends

Answer 1

Step1: Specific resistance

1. Specific resistance is defined as the resistance offered per unit length and unit cross-sectional area when a voltage of known value is applied.
2. SI unit of specific resistance is ohm-meter $\left(\Omega m\right)$.
3. Following is the formula of specific resistance:

$\rho =\frac{RA}{L}$, where $\rho$ = Specific resistance, $R$ = Resistance, $A$= Cross-sectional area, $L$ = Length of the wire,

Step2: Factors dependence

By the formula, we can readily see that

1. Specific resistance is directly proportional to the main resistance.
2. It is directly proportional to the area of the conductor.
3. It is inversely proportional to the total length of the conductor.
4. It also depends on the temperature.
5. It depends on the material used in the conductor as well.

Thus, specific resistance depends on the area, resistance, length, temperature and material of the conductor.