Let’s say the original current is I and △R reflects the change in the resistance in a network of any of the branch, then theorem states that you can calculate the change in current at any point of the network introduction has been assumed that e.m.f – 1 △R into the changed branch This happens while the e.m.fs of the all other sources is suppressed and their internal resistances only represents them.

This theorem is useful for the following purposes:

1. When you want to calculate the sensitivity of a bridge network
2. When you want to analyze the network with the varied values of the branch elements. In addition to the same, it is also used for studying those tolerance values and their effects.