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Three capacitors of capacitances 25 , 30 and 45 are connected in parallel to a supply of 100 V. Energy stored in the above combination is E. When these capacitors are connected in series to the same supply, the stored energy is 9xE. The value of x is .
86
Parallel: Cp = 25 + 30 + 45 = 100
Series: 1Cs = 125 + 130 + 145 = 18 + 15 + 10450 = 43450
Cs = 45043
V is the same, EsE = CsCp = 45043 100 = 986
x = 86
Answer: 86
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