Q7 of 52 Page 354

If the length of a wire is halved and its cross-sectional area is doubled, then what would be the resistance of the wire?

(Given, initially the resistance of the wire is R)

The formula of resistance is:


Where, resistivity


Length of the conductor


A = Area of the conductor


If length of the conductor is halved then,


And, the cross sectional area is doubled,





Now,



Thus, we can conclude that the new resistance of the wire when the area of wire is doublead and length is haved become � the initial resistance.


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