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The length of a potentiometer wire is 1m...

The length of a potentiometer wire is 1m and its resistance is `4Omega` A current of 5 mA is flowing in it. An unknown source of emf is balanced on 40 cm length of this wire, then find the emf of the source.

Text Solution

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`x = I rho =I R/L =(5 xx 4)/1 = 20 mV`
`E = 1 x =0.40 xx 20= 8 mV`
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