How Do You Calculate Equivalent Capacitance and Charge in a Complex Circuit?

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apatuka
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Homework Statement


Find the equivalent capacitance of the capacitor combination, Ct and the charge over C5:Q5
Vab=10V
C1=3uF
C2=11uF
C3=12uF
C4=6uF
C5=9uF

Homework Equations



1) 1/Ct=1/C1+1/C4 = 2uF
2) 1/Ct= 1/C2+1/C5 = 99/20uF

Parallel:
2+99/20+12=379/20uF

Ct=379/20 uF

Charge over Q5:C5

Im failing at this part:
Q5=C5=V

The Attempt at a Solution


Im failing at this part:
Q5=379/20*10-6= 1.895-4uC
 
Attachments
  • Circuit schematic of a bridge-style capacitor network with terminals a and b, labelled c1 to c5, and values Vab=10V, C2=11uF, C4=6uF, C1=3uF, C3=12uF, C5=9uF.
    ph1.JPG
    16.6 KB · Views: 514
  • Diagram of two point charges, Q2 black (negative) and Q1 red (positive), with a triangle of distances 2.0, 2.2 and 2.1 and points a, b, c, d marked, plus the text Q1=11uC and Q2=7uC.
    ph2.JPG
    16 KB · Views: 482
  • Circuit schematic of a capacitor network with capacitors labelled C1, C2, C3, C4, C5, C6, C7 and C8, and terminals marked Vab at the left.
    ph3.JPG
    20.1 KB · Views: 562
Hi apatuka, welcome to PF.
In the given circuit, the charges on C2 and C5 are the same. The voltage across them is given. Find the charge. Then find Q5:C5