Q25. (a)

Loop ADbaCB, (Q₁ / 4) + (Q₁ / 2) + (Q/2) - 12 = 0

Loop ADCB, ( Q-Q₁ / 4 ) + (Q/2) - 12 = 0

Solving these equations, Q₁ = 48 / 11

So, V_ba = Q₁ / C = 12/11 = 1.09 V

(b)

        or         

So, V = 48/ 6 = 8V, Thus V_b - V_a = -8 V.

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