A question with capacitor and a switch

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SUMMARY

The discussion centers on a circuit analysis involving capacitors C1, C2, and C3, where C1 is a 15 microfarad capacitor connected to a 100V battery. Upon switching to position B, C1, C2 (20 microfarads), and C3 (30 microfarads) are arranged in series, resulting in a total capacitance of 6.66 microfarads. The charge on capacitors C2 and C3 is calculated to be 667 microcoulombs, while the charge on C1 is incorrectly noted as 833 microcoulombs, highlighting a misunderstanding of charge distribution in series circuits.

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  • Knowledge of the formula Q=CV for calculating charge on capacitors.
  • Familiarity with basic circuit theory, including voltage sources and charge conservation.
  • Ability to perform calculations involving microfarads and microcoulombs.
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  • Learn about the behavior of capacitors when initially charged and then switched in a circuit.
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Homework Statement


Initially, the switch is in position A and capacitors and are uncharged. Then the switch is flipped to position B. Afterward, what are the charge on and the potential difference across each capacitor?

Position a is a 100V battery and a 15microF capacitor C1. Position B is C1 C2 and C3 in series with C2 being 20 microfarads and C3 30 microfarads.

Homework Equations



Q=CV

The Attempt at a Solution


I found the total capacitance which was 6.66uF, and the Q od C2 and C3 is 667uC which works for Q=CV. However Q1 is 833uF and I have no idea why! I know C in series all have same Q but C1 was charged first so i have no idea!
 
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First, Farads are units of capacitance not charge.
 
i know i meant 833uC
 

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