Use Kirchhoff’s rules to determine the potential difference between the points A and D. When no current flows in the arm BE of the electric network shown in the figure.

Since no current is flowing through the arm BE, we can use Kirchoff’s rules along the path ABED.
From A to B, drop in potential=6V
From B to E, since no current flows through the resistor, potential drop=3V
There is no change in potential from E to D. Hence the total potential drop from A to D =9V