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(A) The resistance $R$ of a wire is given by $R = \frac{ho l}{A}$.Since the volume $V = A 	imes l$ is constant,we can write $A = \frac{V}{l}$.Subst

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Four times

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(A) The resistance $R$ of a wire is given by $R = \frac{ho l}{A}$.Since the volume $V = A 	imes l$ is constant,we can write $A = \frac{V}{l}$.Substituting this into the resistance formula: $R = \frac{ho l}{(V/l)} = \frac{ho l^2}{V}$.Since $ho$ (resistivity) and $V$ (volume) are constant,we have $R \propto l^2$.When the length $l$ is doubled $(l' = 2l)$,the new resistance $R'$ becomes $R' \propto (2l)^2 = 4l^2$.Therefore,$R' = 4R$,which means the resistance becomes four times the original value.

$A$ cylindrical wire is stretched such that its length is doubled but its volume remains constant. The resistance of the wire will become.......

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