Answer:
The new resistance becomes half of the initial resistance.
Explanation:
The resistance of a wire is given by :
[tex]R=\dfrac{\rho L}{A}[/tex]
[tex]\rho[/tex] = resistivity of material
L and A are linear dimension
If the electrical wire is replaced with one having every linear dimension doubled i.e. l' = 2l and r' = 2r
New resistance of wire is given by :
[tex]R'=\dfrac{\rho L'}{A'}[/tex]
[tex]R'=\dfrac{\rho (2L)}{\pi (2r)^2}[/tex]
[tex]R'=\dfrac{1}{2}\dfrac{\rho L}{A}[/tex]
[tex]R'=\dfrac{1}{2}R[/tex]
The new resistance becomes half of the initial resistance. Hence, this is the required solution.
