Finding possible combinations of capacitors given circuit capacitance

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Homework Statement
Please see below
Relevant Equations
Please see below
For this problem,
Printed textbook problem: "Why is the following situation impossible?" A technician needs a capacitance of 7/3 C instead of C, and has three identical capacitors of capacitance C to combine, with the combination placed in parallel with the original capacitor.

The solution is,
Typeset solution text: the extra capacitance must be 7/3 C - C = 4/3 C; listed combinations of one, two and three capacitors (C, 2C, 1/2 C, 3C, 1/3 C, 2/3 C, 3/2 C) show none equals 4/3 C, so it cannot be achieved.

Is the only way of finding the possible combinations is by drawing out circuit diagrams?

Many thanks!
 
Callumnc1 said:
Homework Statement:: Please see below
Relevant Equations:: Please see below

For this problem,
View attachment 322007
The solution is,
View attachment 322008
Is the only way of finding the possible combinations is by drawing out circuit diagrams?

Many thanks!

Drawing a circuit diagram surely helps when you are trying to figure out the capacitance for each particular configuration. However, if you intensely dislike drawing circuit diagrams, you can always look at the list that you posted above.
 
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Callumnc1 said:
Homework Statement:: Please see below
Relevant Equations:: Please see below

For this problem,
View attachment 322007
The solution is,
View attachment 322008
Is the only way of finding the possible combinations is by drawing out circuit diagrams?

Many thanks!
I think so. For such a small case a closed formula doesn't make sense to me and for very many passive circuit elements like resistors, capacitors or coils I am quite sure to not have a closed mathematical formula at all - plus, there is no usage for such a general case.
 
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