Resistivity Dependence on Material
Resistivity is a fundamental property of a substance that quantifies how strongly it resists electric current. It is an intrinsic characteristic of the material itself.
The formula relating resistance ($R$), resistivity ($\rho$), length ($L$), and cross-sectional area ($A$) is given by:
$ R = \rho \frac{L}{A} $
Analysis of Factors
- Material: Resistivity ($\rho$) is inherent to the material. For example, copper has a much lower resistivity than rubber. This is the primary factor.
- Number of wires: This relates to quantity, not the intrinsic property of the material.
- Diameter of the wire: Diameter affects the cross-sectional area ($A$). While area influences resistance ($R$), it does not change the material's resistivity ($\rho$).
- Length of the wire: Length ($L$) directly influences resistance ($R$) but does not alter the resistivity ($\rho$) of the material.
Key Takeaway
Resistivity is solely dependent on the nature of the Material and, to some extent, temperature (though material is the main factor). Dimensions like length and diameter affect resistance, not resistivity.
Similar Questions
- The resistance of a metallic wire of length 1m and area of cross-section 1sq.metre having a resistivity is $2 \times 10^{-6}$ ohm - m is:
When a number of resistance are connected in _______, their combined resistance is less than the smallest individual resistance.
Important Questions from Resistance and Resistivity
Which of the following statements are correct about the electrical resistance and resistivity of a wire?
1. Both quantities depend on the area of cross-section of the wire
2. Both depend on the temperature
3. Resistance of the wire is directly proportional to the resistivity of the wire
4. Resistivity of the wire is directly proportional to the length of the
wireSelect the correct answer using the code given below:
A circular coil of single turn has a resistance of 20 Ω. Which one of the following is the correct value for resistance between the ends of any diameter of the coil?
Let us consider a copper wire having radius r and length l. Let its resistance be R. If the radius of another copper wire is 2r and the length is l/2 then the resistance of this wire will be
If the length of a conductor is doubled, then the resistance of the conductor will be: (other parameters are kept same)
Which factor does NOT affect the resistivity of a material?
