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Figure shows a potentiometer in which R ...

Figure shows a potentiometer in which R is variable resistance. AB is uniform wire of length 100cm having resistance r. In an experiment R = 0 then null deflection is at 30 cm from A and for R = x null deflection is at 60 cm from A. The value of x is

A

`r/2`

B

`(3r)/2`

C

2r

D

r

Text Solution

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The correct Answer is:
D
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