The electrical resistance of a wire depends on which of the following?

The correct answer is Option (4) → All of the above

The resistance of a wire is \( R=\displaystyle\frac{\rho L}{A} \), where \(\rho\) is the resistivity of its material, \(L\) its length and \(A\) its area of cross-section.

• A longer wire has more resistance, as \(R\) is proportional to \(L\)

• A thicker wire has less resistance, as \(R\) is inversely proportional to \(A\)

• A material with higher resistivity, such as nichrome compared with copper, gives more resistance

All three factors affect the resistance.