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Question
A potentiometer wire has a length of 1.5 m and a resistance of 10 Ω. It is connected in series with the cell of emf 4 Volt and internal resistance 5 Ω. Calculate the potential drop per centimeter of the wire.
Solution
Given: L = 1.5 m, R = 10 Ω, E = 4 V, r = 5 Ω.
K =
∴ K =
The potential drop per centimetre of the wire is
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