AB is a potentiometer wire (Fig). If the value of R is increased, in which direction will the balance point J shift?
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If the value of R is increased, the current through the wire will decrease which in turn decreases the potential difference across AB, and hence potential gradient (k) across AB decreases.
Since, at neutral point, for given emf of cell, l increases as potential gradient (k) across AB has decreased because E' = kI
Thus, with the increase of l, which will result in increase in balance length. So, jockey J will shift towards B.
Since, at neutral point, for given emf of cell, l increases as potential gradient (k) across AB has decreased because E' = kI
Thus, with the increase of l, which will result in increase in balance length. So, jockey J will shift towards B.
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