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Question
A potentiometer wire has length of 2m and resistance 10Ω. It is connected in series with resistance 990Ω and a cell of e.m.f. 2V. Calculate the potential gradient along the wire.
Solution
Given: L = 2 m, R = 10 Ω, RE = 990 Ω
E = 2 V
To find: Potential gradient of wire (K)
Formula: `K = V/L`
∴ K = 10-2 V/m = 0.01 V/m
The potential gradient of wire is 0.01 V/m.
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