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प्रश्न
A given metallic wire of resistance R is doubled on itself. What will be its new resistance?
उत्तर
When a given metallic wire is doubled on itself, its length is reduced to half, but its area of cross-section gets doubled. So, the resistance of the wire will become one-fourth i.e., the new resistance of wire will be R/4 (or 0.25 R).
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