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Question
Three capacitors of capacitances 2 pF, 3 pF and 4 pF are connected in parallel. Determine the charge on each capacitor if the combination is connected to a 100 V supply.
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Solution
Given: Supply voltage, V = 100 V
In a parallel combination, the potential difference across each capacitor is the same.
V1 = V2 = V3 = 100 V
Charge on a capacitor of capacitance C and potential difference V is given by the relation,
q = CV
For C1 = 2 pF,
q1 = C1V1
= 2 × 100
= 200 pC
= 2 × 10−10 C
For C2 = 3 pF,
q2 = C2V2
= 3 × 100
= 300 pC
= 3 × 10−10 C
For C3 = 4 pF,
q3 = C3V3
= 4 × 100
= 400 pC
= 4 × 10−10 C
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