Resistance of a wire is r ohms. The wire is stretched to double its length, then its resistance is ohms is?

Answer: 4r
Explanation

When a wire is stretched to double its length, its resistance becomes:

R' = ρ × (2L) / (A/2) = 4 × R

So, the new resistance is 4r ohms

This question appeared in Past Papers (2 times)
KMU CAT Past Papers and Syllabus (2 times)
This question appeared in Subjects (2 times)
EVERYDAY SCIENCE (2 times)

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