# Find value of capacitance C?

• help me pls
In summary, the conversation is discussing how to find the value of capacitance C in a circuit with multiple capacitors, given that the equivalent capacitance is 9.22 microFarads. The equations used include 1/Cs=(1/C1)+(1/C2) for series circuits and Cp=C1+C2 for parallel circuits. The attempt at a solution involves simplifying the circuit and setting up the correct equation, but there is an error in the calculation leading to a different result than the expected 2.558 microFarads. The conversation then discusses resolving the circuit in the correct order, taking into account the brackets.

## Homework Statement

The equivalent capacitance of the capacitors shown in Figure 21-41 is 9.22 microFarads. Find the value of capacitance C.

## Homework Equations

Ok so this has to deal with Ceq, and it is a combonation of series and parallel circuits. Knowing this, I can use for series 1/Cs=(1/C1)+(1/C2) and so on. For parallel, it is Cp=C1+C2 and so on.

## The Attempt at a Solution

Looking at the picture, the givens is Ceq = 9.22 microFarads. I first simplify the circuit so that it shows 3 parallel circuits, which are 7.22 microFarads, ((4.25C)/(4.25+C),and 4.92. Setting up the equation, i get C to equal something not 2.56 microfarads. What did i do wrong?

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help me pls said:
3 parallel circuits, which are 7.22 microFarads, ((4.25C)/(4.25+C),and 4.92.
I would calculate that again (there's an error here). Look at the circuit carefully.
(btw. you SHOULD get 2,558microF)

Not exactly 3 parallel circuits but 7.22 in parallel with (C in series with (4.25 in parallel with (12.0 in series with 8.35)))

That's correct but you have to resolve them in the right order taking into account the brackets eg...

"12.0 in series with 8.35"
then
"4.25 in parallel with" the above
then
"C in series with" the above
etc

However this bit..
help me pls said:
((4.25C)/(4.25+C),
suggests you did
"C in series with 4.25"
or something like that.