In the circuit shown the cell is idea with end `=15V` each resistance is of `3Omega` The potential difference the capacitor is

Options

A. zero
B. `9V`
C. `12V`
D. `15V`

Answer

C

Explanation

Since fully charged capacitor draws no currents .Therefore, no current flows in arm `GHF` so the resistance `R` of arm `BF` ineffective .The total resistance of other resistance in circuit is
`R' = ((R+R) xxR)/((R + R)+R) + R= (6 xx 3)/(6+3) + 3 = 5 Omega`
Total current, `I = (E )/(R') = (15)/(5) = 3A`
Since in parrelel circuit the current divides in the inverse ratio of resistance so current in arm `ABGD` So pot diff between `G` and `D`
`= V_(G) - V_(D) = 1 xx 3= 3V`
Pot diff between `D` and `F`
`= V_(D) - V_(F) = 3 xx 3 = 9V`
`:. V_(G) - V_(F)(V_(G) - V_(D)) + (V_(D) - V_(F))`
`= 3+9 = 12V`
Pot diff across capacitior `= V_(G) - V_(F) = 12 V`