The current in the primary circuit of a potentiometer is `0.2 A`. The specific resistance and cross-section of the potentiometer wire are `4xx10^(-7)`

Monjur Alahi

The current in the primary circuit of a potentiometer is `0.2 A`. The specific resistance and cross-section of the potentiometer wire are `4xx10^(-7)` ohm meter and `8xx10^(-7)m^(2)` respectively. The potential gradient will be equal to -
A. `1(V)/(m)`
B. `0.5(V)/(m)`
C. `0.1(V)/(m)`
D. `0.2(V)/(m)`


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Salim Ahmed Kawsar

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Correct Answer - C
`V=irhol`

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