The correct answer is Option (3) → (A), (C) and (D) only
The resistance ($R$) of a conductor depends on several physical properties of the material and its dimensions. These relationships are defined by the formula:
$R = \rho \frac{l}{A}$
Where:
- $R$ is the Resistance.
- $\rho$ (rho) is the Resistivity (nature of the material).
- $l$ is the Length.
- $A$ is the Area of cross-section.
Step-by-Step Breakdown:
- (A) Its length: Resistance is directly proportional to length ($R \propto l$). If the length increases, the electrons have to travel a longer distance, encountering more collisions.
- (B) Its weight: Resistance does not depend on the weight of the conductor. While weight is a property of the mass, it does not directly affect the flow of electrons.
- (C) Its area of cross-section: Resistance is inversely proportional to the area of cross-section ($R \propto 1/A$). A thicker wire (larger area) provides more space for electrons to flow, reducing resistance.
- (D) The nature of its material: Different materials have different atomic structures, which determines their resistivity ($\rho$). For example, copper has much lower resistance than iron for the same dimensions.
Conclusion:
The factors are (A), (C), and (D). |
