Two known resistances are connected in two gaps of a meter bridge. The null point is obtained at 20 ~cm from zero end. A resistance of 15 is connected in series with the smaller of the two. The null point shifts to 40 ~cm . The smaller resi

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Two known resistances are connected in two gaps of a meter bridge. The null point is obtained at 20 ~cm from zero end. A resistance of 15 is connected in series with the smaller of the two. The null point shifts to 40 ~cm . The smaller resistances is

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Correct answer: A. 9

Given l=20 ~cm l^ =40 ~cm Using R₁ R₂ = l 100-l aligned & R₁ R₂ = 20 100-20 & R₂=4 R₁ aligned Again using R₁ R₂ = l^ 100-l^ , where l^ =40 ~cm , R₁=R^ ₁+15 and aligned & R₂^ =R₂=4 R₁ & R₁+15 4 R₁ = 40 100-40 & R₁=9 aligned

Two known resistances are connected in two gaps of a meter bridge. The null point is obtained at 20 ~cm from zero end. A resistance of 15 is connected in series with the smaller of the two. The null point shifts to 40 ~cm . The smaller resistances is

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