Three capacitors of capacitances 2 pF, 3 pF and 4 pF are connected in parallel.

(a) What is the total capacitance of the combination?


(b) Determine the charge on each capacitor if the combination is connected to a 100 V supply.

Given, C1 = 2 pF

C2 = 3 pF


C3 = 4 pF , V = 100 volt



(a) Total capacitance of the parallel combination is


C = C1 + C2 + C3 = 2 + 3 + 4 = 9 pF


(b) Let q1 , q2 and q3 be that charges on the capacitor C1 , C2 and C3 respectively.


In the parallel combination the potential difference across each capacitor will be equal to the supply voltage i.e., 100 V


⇒ q1 = C1V = 2 x 10-12 × 100 = 2 × 10-10 C


⇒ q2 = C2V = 3 x 10-12 × 100 = 3 × 10-10 C


⇒ q3 = C3V = 4 x 10-12 × 100 = 4 × 10-10 C


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