Answer:
0.84ÎŒF
Explanation:
Charge is same through both the capacitors since they are in series. Total voltage is the sum of the voltages of the individual capacitors.. So voltage across the 2nd capacitor is 120- 90 =30 V.
Charge across first capacitor is Q = CâVâ = 90 x0.28 = 25.2ÎŒC
Therefore capacitance of 2nd capacitor =
Câ = QĂ·Vâ = 25.2Ă·30 = 0.84 ÎŒF
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