JEE Mains · Physics · STD 12 - 3. current electricity
If a copper wire is stretched to increase its length by \(20 \% \). The percentage increase in resistance of the wire is \(..........\%\)
- A \(40\)
- B \(41\)
- C \(44\)
- D \(43\)
Answer & Solution
Correct Answer
(C) \(44\)
Step-by-step Solution
Detailed explanation
As volume is constant, So resistance \(\propto\) (length \()^2\) \(\Rightarrow \% \text { change in resistance }=20+20+\frac{400}{100}=44 \%\)
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