engineering recuitment AAI ATC Junior Executive 2025 Mock Test Series Physics Current, Resistance and Electricity Resistance and Resistivity
A conducting wire has length \(L_1\) and diameter \(d_1\). After stretching the same wire length becomes \(L_2\) and diameter \(d_2\). The ratio of resistances before and after stretching is
1
\(d_{2}^{4} : d_{1}^{4}\)
2
\(d_{1}^{4} : d_{2}^{4}\)
3
\(d_{2}^{2} : d_{1}^{2}\)
4
\(d_{1}^{2} : d_{2}^{2}\)