Find Value of 2nd Capacitor in Series w/ Known 1st

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To find the value of a second capacitor in series when the first capacitor's capacitance is known, the total capacitance must also be known. The relationship for capacitors in series is defined by the equation 1/C_tot = 1/C_1 + 1/C_2. With the known values of C_tot and C_1, C_2 can be calculated easily. Additionally, understanding the charge and potential can also aid in solving for the unknown capacitance using the formula C = Q/V. Accurate problem-solving requires listing given values and relevant equations for clarity.
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if there are two capacitors in series and the capacitance of one is known how would i find a value for the other?
 
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dan greig said:
if there are two capacitors in series and the capacitance of one is known how would i find a value for the other?

I am assuming that you know the total capacitance (the capacitance of the two combined), right? Otherwise it's impossible to answer:eek:

For two capacitors in series, the total capacitance is given by
{1 \over C_{tot}} = {1 \over C_1} + {1 \over C_2}, ore, if you prefer C_{total} = { C_1 C_2 \over C_1 + C_2}.

You know the total capacitance and C_1 (say). Then you can easily solve for C_2.

Patrick
 
{1 \over C_{tot}} = {1 \over C_1} + {1 \over C_2}

Well, what is the exact problem? Like he said above, you would need to know the total capacitance, OR the charge and the potential :-) seeing how C=Q/V. When dealing with electricity, capacitors, and resistors... It's best to write down what you are given, have a list of equations next to you and look at the equations to see which ones match up with what you need :-)
 
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