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Question
In a potentiometer experiment, the balancing length with a resistance of 2Ω is found to be 100 cm, while that of an unknown resistance is 500 cm. Calculate the value of the unknown resistance.
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Solution
`R = 2 Ω`
`l_R = 100 "cm"`
`X = ?`
`l_X = 500 "cm"`
`therefore` by balancing bridge condition
`R/X = l_R/l_Y`
`2/X = 100/500`
`X = 10 Ω`
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