CBSE Class 12-science Answered

In case of parallel arrangement, one end of all capacitors is attached to the same junction and the other end of all capacitors is connected to each other at another junction. The potential difference is the same across each of them.

The charge on each capacitor will not necessarily be the same if they have different capacitances because while the charging of the capacitors, the charges developed across the capacitor plates will be proportional to the capacitance of each capacitor since q=C V and V is the same for capacitors in parallel.

Now, for two capacitors in parallel, the total charge Q stored across an equivalent capacitor is divided between the two capacitors. Let the charges be Q₁ and Q₂. 
Thus

Q = Q₁ + Q₂
Then we can write

But  and since the potential difference or voltage V is the same across each capacitor.

Hence, the equivalent capacitance of a set of capacitors in parallel is the sum of the individual capacitance.