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Question
What are the advantages of the null-point method in a Wheatstone bridge? What additional measurements would be required to calculate `R_(unknown)` by any other method?
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Solution
The advantage of the null point method in a Wheatstone bridge is that the resistance of galvanometer does not affect the balance point and there is no need to determine the current in resistances and galvanometer and the internal resistance of a galvanometer. `R_(unknown)` can be calculated by applying Kirchhoff’s rules to the circuit. We would need additional accurate measurements of all the currents in resistances and galvanometer and internal resistance of the galvanometer.
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