An unknown resistance r si determined in terms of a standared resistance R = 100 Omega by using potentiometer. The potential difference across r is balanced againt 45 cm length of the wire and that (r + R) is obtained at 70 cm of the wire. Find the value of the unknown resistance.

An unknown resistance r si determined in terms of a standared resistan

1.	An unknown resistance r si determined in terms of a standared resistance R = 100 Omega by using potentiometer. The potential difference across r is balanced againt 45 cm length of the wire and that (r + R) is obtained at 70 cm of the wire. Find the value of the unknown resistance.
Answer» `200 Omega` `280 Omega` `180 Omega` `100 Omega` Solution :`l_(1) = 45 cm, l_(2) = 70 cm` `R = 100 Omega` `r = R ((l_(1))/(l_(2) - l_(1))) = 100 ((45)/(75 - 45)) = 180 Omega`

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An unknown resistance r si determined in terms of a standared resistance R = 100 Omega by using potentiometer. The potential difference across r is balanced againt 45 cm length of the wire and that (r + R) is obtained at 70 cm of the wire. Find the value of the unknown resistance.

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