alleryStart learning →The resistance of a metallic wire is
Adirectly proportional to its area of cross-section
Bdirectly proportional to its length
Cinversely proportional to its length
Dindependent of the material
Answer & Solution
Correct answer: B. directly proportional to its length
1. R = ρl/A.
2. So resistance is **directly proportional to length l** and inversely proportional to area A.
3. A longer wire (or a thinner wire) has more resistance; the material's resistivity ρ also matters.
_Source: Karnataka SSLC (KSEEB) Class 10 Science, Ch12 'Electricity', §12.4 (R = ρl/A)_
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