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Question
How does the resistance of a wire depend on its radius? Explain your answer.
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Solution
Resistance of a wire is inversely proportional to the area of cross-section of the wire.
`R ∝ 1/"r"^2 or R prop 1/"a" or R ∝ 1/"𝜋𝑟"^2`
where 'a' is the area of cross-section and r is the radius of wire and R is the resistance. In other words thick wire offers less resistance and thin wire offers more resistance. In thick conductor electrons suffer less collisions.
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