Oh I am just checking the solution you gave up there. The V effective is the resulting PD across the two Capacitors.
I tend to think that when connected in series, the charge in any two Capacitors tend to oppose one another so that is why they are being subtracted. Oh this is confusing even me...
The +ve to -ve connection means that two anr now connected in series(That is what basic circuitry says)
Let us now analyse the question:
( E means x10 to power)
5uF charged at Pd of 24v
6uF charged at Pd of 12V
The charge stored in the 5uF capacitor = Q1= CV=5E-6 Fx24=1.2E-4C
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