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प्रश्न
The resistance of a wire of 0.01 cm radius is 10 Ω. If the resistivity of the wire is 50 × 10-8 Ω, find the length of this wire.
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उत्तर
Given, Radius, r = 0.01 cm = 0.0001 m
Resistance, R = 10 Ω
Resistivity, `rho = 50 xx 10^-8` Ω m
R = `rho "L"/"A"`
L = `"RA"/rho`
`= (10 xx 3.14 xx (0.0001)^2)/(50 xx 10^-8)`
= 0.628 m
Hence, the length of the wire is 0.628 m.
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