A `2muF` capacitor is charged to a potential of 20V. Another `3muF` uncharged capacitor is connected in parallel with the first capacitor. What would be the terminal potential difference of the combination? Find out the charges on the two capacitors?

Explanation

Initially, the charge on the first capacitor,
`Q_1= C_1V_1= (2xx10^(-6))xx20= 40xx10^(-6)C`
and charge on the second capacitor, as it was uncharged, `Q_2=0`.
Net charge, `Q= Q_1+Q_2= 40xx10^(-6)C`
Equivalent capacitance of the parallel combination,
`C = C_1+C_2= (2+3)muF = 5xx10^(-6)F`
Terminal potential difference of the combination,
`V = (Q)/(C ) = (40xx10^(-6))/(5xx10^(-6))= 8V`
Charge on the capacitor,
`Q_1' = C_1V = (2xx10^(-6))xx8= 16xx10^(-6)C = 16 muC`
and charge on the second capacitor,
`Q_2 = C_2V = (3xx10^(-6))xx8= 24xx10^(-6)C = 24muC`.