A uniform metallic wire of resistance R is stretched uniformly until its length is doubled without any change in its volume. What will be the new resistance of the stretched wire?

💡 Solution & Explanation

When a wire is stretched to twice its original length while keeping its volume constant, its cross-sectional area decreases by a factor of two. Resistance is directly proportional to length and inversely proportional to cross-sectional area, meaning doubling the length while halving the area increases the total resistance by a factor of four. Alternative responses incorrectly assume a linear relationship with length alone. Resistivity of the metallic material remains entirely constant during this geometrical deformation.