Why Does a Galvanometer Show Zero Deflection Despite Potential Differences?

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    Conceptual Potentiometer
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SUMMARY

The discussion centers on the behavior of a galvanometer in a potentiometer circuit when the potential difference between points A and J equals the electromotive force (emf) of the cell. It is established that if the potential difference between A and J matches the emf, no current flows through the galvanometer, resulting in zero deflection. The confusion arises when considering the potential differences between A, J, and the battery terminals, but it is clarified that node A and the positive terminal of the battery are the same, preventing any voltage difference that would cause current flow.

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abhijit.k939
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Potentiometer conceptual help!

The book that i am using currently states that "If the potential difference between A and J is equal to the emf of the cell, no current flows through the galvanometer. It shows zero deflection."
But suppose A be at 10V and J at 5V, and The +ve terminal of battery at 5V and negative at 0V
Therefore the Potential Difference between AJ and the emf of cell are same ,
but the pottential difference between A and +ve terminal of cell is 5V so current should flow, same for J and -ve terminal.So there should be deflection in galvanometer due to flow of current.Then why not?

Note: A and J are connected to the driving circuit as well as the battery to be measured

I wasnt able to post link for the image directly
http:+//tinypic.com+/r/4kw+7yx/6 (Remove all the + signs)
 
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abhijit.k939
It looks from your schematic that node A and the +ve terminal of the battery are the same node. This would prohibit them from being at different voltages.
 

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