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Questions
Will current flow more easily through a thick wire or a thin wire of the same material, when connected to the same source? Why?
Will current flow more easily through a thick wire or a thin wire of the same material when connected to the same source? Give reason for your answer.
Solution 1
The current will flow more easily through thick wire. It is because the resistance of a
conductor is inversely proportional to its area of cross-section. If thicker the wire, less is resistance and hence more easily the current flows.
Solution 2
Resistance (R) is inversely proportional to the area of the cross-section (A) of the
wire. So, thicker the wire, lower is the resistance of the wire and vice-versa.
Therefore, current can flow more easily through a thick wire than a thin wire.
`R = rho xx l/A`
`R ∝ 1/A`
Solution 3
The resistance of a conductor is inversely proportional to its area of cross-section, i.e. `R ∝ 1/A`. So as the conductor is a thick wire, its resistance decreases and current will flow easily through it, in comparison with a thin wire.
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