__ Problem 3.2__ Source:
Problem 25.23 - page 134 - HALLIDAY, RESNICK,
WALKER, Jearl - Book: Fundamentos de Física - Vol 3 - Ed. LTC - 8ª edição - 2009.

In the circuit shown in _{2} = 3 µF,
C_{4} = 4 µF

_{3}

_{1}

__Solution of the Problem 3.2__

**Item a**

Let's start analyzing the circuit by the capacitor _{4}_{4} = 8 µC

Doing the calculations with the data that we have and based
in the above equation, we can calculate the
potential difference between the terminals of the _{4}

Note that the voltage on _{3}_{4}_{3}_{3} = 4 µC_{3}

**Item b**

As we know that by point _{1}_{2}_{2} = 12 µC_{2} = 3 µF

We must remember that in a series of capacitors, the charge on
each capacitor in the circuit is the same. Therefore _{1}_{2}_{1} = 12 µC_{1}_{C4}_{C2}_{C1} = 3 volts_{1}