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प्रश्न
A 10 m long wire of a particular material is of resistance 5Ω What will be the resistance if the wire is doubled itself.
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उत्तर
Given: The resistance of 10 m long wire = 5 Ω
On doubling the wire on itself the length is reduced to half and the area of cross-section is doubled so the resistance is reduced to one-fourth i.e. the resistance of the wire will become:
`1/4 xx 5 Omega = 1.25 Omega`
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