Question

the resistance of a metallic wire is 10ohm , length 2m and diameter is 0.5mm find the resistivity of the wire when length is doubled​

Answer 1

Answer:

$resistnce = \frac{ro \times l}{area} \times \frac{l}{l} = \frac{ro \times {l}^{2} }{volume} \\ so \: volume \: will \: be \: constant \\ r \: is \: directly \: propotional \: to \: {l}^{2} \\ \frac{10}{r} = \frac{4}{16} \\ r = 40 \: ohm$

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