The resistance \(R\) of a uniform metallic conductor is directly proportional to its length (\(L\)) and inversely proportional to its cross-sectional area (\(A\)). This relationship is described by the following equation:
\(R = \rho \frac{L}{A}\)
where \(\rho\) (rho) is the resistivity of the material. Resistivity is a material property that reflects how strongly a material opposes the flow of electric current. Different materials have different resistivities. Therefore, the resistance of a conductor depends on:
- Length (\(L\)): A longer conductor has higher resistance because the electrons have to travel a greater distance.
- Area of cross-section (\(A\)): A larger cross-sectional area means there are more pathways for electrons to flow, thus reducing resistance.
- Nature of the material (\(\rho\)): The material's resistivity determines how easily electrons can move through it. A material with high resistivity will have a higher resistance.
Option 1, 2, and 3 are incorrect because they only consider one factor. Option 4 correctly identifies all three factors that influence the resistance of a uniform metallic conductor.
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:
- Resistivity of the wire depends on mainly ________
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?
