Question

What is the potential difference across the galvanometer at null point?

Answer 1

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So, the potential at point B becomes equal to the potential at point D hence the potential difference between these two points is zero hence currentthrough galvanometer is nil. The deflection in the galvanometer is nilwhen the switch K2 is closed.

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Answer 2

Hey friend....

The potential difference across the end is "zero". When the galvonometer is at null point.

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