The length of the wire is doubled. Its conduc | vedclass

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(B) The resistance $R$ of a wire is given by $R = \rho \frac{l}{A}$,where $\rho$ is resistivity,$l$ is length,and $A$ is the cross-sectional area.Cond

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Halved

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(B) The resistance $R$ of a wire is given by $R = \rho \frac{l}{A}$,where $\rho$ is resistivity,$l$ is length,and $A$ is the cross-sectional area.Conductance $C$ is the reciprocal of resistance,so $C = \frac{1}{R} = \frac{A}{\rho l}$.From this expression,it is clear that $C \propto \frac{1}{l}$.If the length $l$ is doubled $(l' = 2l)$,the new conductance $C'$ becomes $C' = \frac{A}{\rho (2l)} = \frac{1}{2} \left( \frac{A}{\rho l} \right) = \frac{1}{2} C$.Therefore,the conductance is halved.

The length of the wire is doubled. Its conductance will be

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