Evaluate the potential difference V_a - V_b between points a and b for the circuit designated as (d) in the figure.

Step-by-step solution

In the circuit labeled (d), let the potential at node a be V_a = 0 . The circuit consists of three parallel branches connected between nodes a and b . Each branch contains a battery and a capacitor in series. For all three batteries, the positive terminal (longer line) is oriented towards the right. The potentials at the intermediate nodes between the batteries and capacitors are 6 V (top branch), 12 V (middle branch), and 24 V (bottom branch). Applying the principle of charge conservation for the isolated plates c