A 1 m long wire is broken into two unequal parts X and Y. The X part of the wire is stretched into another wire W. Length of W is twice the length of X and the resistance of W is twice that of Y. Find the ratio of length of X and Y.
- 1:4
- 1:2
- 4:1
- 2:1
The Correct Option is B
Solution and Explanation
Rw = 2Ry
\(ρ\frac{2x}{\frac{A}{2}}=\frac{2ρ(1−x)}{A}\)
4x = 2(1 – x)
\(\frac{x}{1−x}=\frac{1}{2}\)
So, the correct option is (B): 1:2
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