Question

determine the resistance of a copper wire having a length of 1 km and diameter of 0.2 mm​

Answer 1

Answer:

$Hello!</p><p></p><p>• \bf\small{ANSWER}ANSWER :</p><p></p><p>\boxed{\red{\sf 85\: \varOmega}}85Ω</p><p></p><p>• \bf\small{EXPLANATION}EXPLANATION :</p><p></p><p>\begin{gathered}\star \: \sf Length, L = 1000\:m \\ \star \: \sf Diameter, D = 0.50 mm \\ \\ \sf Then, \\ \\ \star \: \sf r = 0.25 \:mm = 0.25\times10^{-3} \:\end{gathered}⋆Length,L=1000m⋆Diameter,D=0.50mmThen,⋆r=0.25mm=0.25×10−3</p><p>        </p><p>\star⋆ \sf Resistivity, \:pResistivity,p = 1.7 \times 10^{-8}1.7×10−8</p><p></p><p>Now,</p><p></p><p>\bf\small{R}R = \dfrac{1.7 \times 10^{-8} \times 1000}{0.25\times 10^{-3}} = \boxed{\red{\sf 85\: \varOmega}}0.25×10−31.7×10−8×1000=85Ω</p><p>$

Answer 2

Answer:

First make uniform measurements units

Copper resistivity is 1,68 x 10 ^ -8 Ohm Meter

Length 1 Km = 1000 m

Diameter = 0.5 mm = 0.005 meter

Area = Pi x D x D /4 = Pi x 0.0005 x 0.0005 /4 = 1.96 x 10^-7 Sq Mtr

Resistance = (Resistivity x Length)/Area

= 1,68 x 10^-8 x 1000 /(1,96 x10^–7 = 857 x 10^-1 = 85.7 Ohms

Explanation:

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