COMEDK · Physics · 19. Current Electricity
If the length of a wire is increased by \(20 \%\) by stretching it, then its resistance is increased to
- A \(22 \%\)
- B \(33 \%\)
- C \(55 \%\)
- D \(44 \%\)
Answer & Solution
Correct Answer
(D) \(44 \%\)
Step-by-step Solution
Detailed explanation
Given \(\begin{aligned} & l_1=l, A_1=A \\ & l_2=l\left(1+\frac{20}{100}\right)=\frac{6 l}{5}, A_2=A^{\prime} \end{aligned}\) We have,…
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