What is the advantage of using thick metallic strips to join wires in a potentiometer?
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Metallic strips have negligible resistance and need not to be counted in the length $l_1,$ of the null point of potentiometer. That's why the thick metallic strips are used in potentiometer. It is for the convenience of experimenter as he measures only their lengths along the straight segments each of lengths $1m.$This measurements is done with the help of a centimetre scale or metre scale and leads to the accurate measurements.
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