A) \[7.5\,\Omega \]
B) \[45\,\Omega \]
C) \[90\,\Omega \]
D) \[270\,\Omega \]
Correct Answer: A
Solution :
Initially : Resistance of given cable \[R=\rho \frac{l}{\pi \times {{(9\times {{10}^{-3}})}^{2}}}\] ... (i) Finally : Resistance of each insulated copper wire is \[R\,'=\rho \frac{l}{\pi \times {{(3\times {{10}^{-3}})}^{2}}}\]. Hence equivalent resistance of cable \[{{R}_{eq}}=\frac{R\,'}{6}=\frac{1}{6}\times \left( \rho \frac{l}{\pi \times {{(3\times {{10}^{-3}})}^{2}}} \right)\]?.(ii) On solving equation (i) and (ii) we get Req = 7.5 WYou need to login to perform this action.
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