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.
(a) Capacitances of the given capacitors are
C1 = 2 pF,
C2 = 3 pF,
C3 = 4 pF,
For the parallel combination of the capacitors, equivalent capacitoris C' given by the algebraic sum,
C'=2 +3 + 4= 9 pF
Therefore, total capacitance of the combination is 9 pF.
(b) Supply voltage, V = 100 V
The voltage through all the three capacitors is same = V = 100 V
Charge on a capacitor of capacitance C and potential difference V is given by the relation,
q = VC … (i)
For C = 2 pF,
Charge= VC = 100 x 2 = 200 pC = 2 x 10-10 C
For C = 3 pF,
Charge = VC = 100 x 3 = 300 pC = 3 x 10-10 C
For C = 4 pF
Charge = VC = 100 x 4 = 400 pC = 4 x 10-10 C
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