Capacitance Ct, Qt problems.

[apatuka]

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

 

[rl.bhat]

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

 

[kerimek]

I can suggest approaching this problem by first understanding the concept of capacitance and its relationship to voltage and charge. Capacitance is a measure of a capacitor's ability to store electric charge, and it is calculated by dividing the charge by the voltage.

In this problem, we have a combination of capacitors connected in parallel and series. To find the equivalent capacitance, we can use the equations for capacitors in parallel and series. For capacitors in parallel, the equivalent capacitance is the sum of individual capacitances, while for capacitors in series, the inverse of the equivalent capacitance is the sum of the inverses of individual capacitances.

Using these equations, we can find the equivalent capacitance of the combination of C1 and C4, which is 2uF. Then, we can find the equivalent capacitance of C2 and C5, which is 99/20uF. Finally, we can add these two equivalent capacitances to the capacitance of C3 to get the total equivalent capacitance, which is 379/20uF.

As for the charge over C5, we know that the voltage across C5 is 10V, and we can use the equation Q=CV to calculate the charge. Plugging in the values, we get Q5=9uF*10V=90uC. So, the charge over C5 is 90uC.

I hope this helps in understanding the problem and finding the correct solution. Remember to always approach problems systematically and use the appropriate equations to solve them.