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प्रश्न
State whether the resistivity of a wire changes with the change in the thickness of the wire.
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उत्तर
`R = (rhoL)/A`
`:. rho = (RA)/L`
`A = pir^2= (R(pir^2))/L`
⇒ Resistivity `ar^2 =>`Thus if thichkness increases resistivity increases.
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