Question
It is required to construct a $10\mu\text{F}$ capacitor which can be connected across a 200V battery. Capacitors of capacitance $10\mu\text{F}$ are available but they can withstand only 50V. Design a combination which can yield the desired result.

Answer

Let there are ‘x’ no of capacitors in series ie in a row
So, x × 50 = 200
⇒ x = 4 capacitors.
Effective capacitance in a row $=\frac{10}{4}$
Now, let there are ‘y’ such rows
So, $\frac{10}{4}\times\text{y}=10$
⇒ y = 4 capacitor.
So, the combinations of four rows each of 4 capacitors.

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