Given, C1=1µF,V=9V, C2=2µF,C3=3µF Equivalent capacitance of C2 and C3 C′=C2+C3=2+3=5µF Common potential difference when C1 and C′ are combined, is given as V′=‌
‌ total charge ‌(Q)
‌ total copacitance ‌(C1+C′)
‌V′=‌
Q
C1+C′
‌‌ But ‌Q=C1V ‌∴V′=‌
C1V
C1+C′
=‌
1×9
1+5
=‌
9
6
=1.5V Charge on capacitor C3 is given as Q3‌=C3V′ ‌=3×10−6×1.5=4.5×10−6C