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Question
An unknown resistance is placed in the left gap and resistance of 50 ohm is placed in the right gap of a meter bridge. The null point is obtained at 40 cm from the left end. Determine the unknown resistance.
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Solution
Given:
`R = 50 Omega`
`l_X = 40 cm = 0.4 m`
`l_R = 60 cm = 0.6 m`
To find: Unknown resistance (X)
Formula: `X=R l_X/l_R`
Solution:
`X=(50xx40)/60`
`X=100/3`
`X=33.33 Omega`
The value of unkown resistance is 33.33 Ω.
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